Knowledge (XXG)

Accumulation point

Source đź“ť

775: 6926: 6709: 6947: 6915: 915: 6984: 6957: 6937: 1118:
It does not make a difference if we restrict the condition to open neighbourhoods only. It is often convenient to use the "open neighbourhood" form of the definition to show that a point is a limit point and to use the "general neighbourhood" form of the definition to derive facts from a known limit
3896: 3015: 477:). Importantly, although "limit point of a set" is synonymous with "cluster/accumulation point of a set", this is not true for sequences (nor nets or filters). That is, the term "limit point of a sequence" is 771:. Indeed, a set is closed if and only if it contains all of its limit points, and the topological closure operation can be thought of as an operation that enriches a set by uniting it with its limit points. 2881: 1978: 3189: 3479: 3338: 3278: 3121: 3242: 2942: 847: 3796: 296: 3709: 2166: 4211: 4156: 3989: 2477: 2052: 6207: 1407: 2364: 6146: 5061: 3950: 3437: 3367: 2314: 899: 754: 676: 2710: 2677: 2235: 2199: 2088: 438: 2748: 2509: 5947: 3597: 3502: 3302: 1755: 3924: 3573: 3045: 2559: 1897: 1351: 1200: 5918: 5892: 5729: 4843: 4660: 4358: 1290: 1168: 654: 5090: 4243: 3791: 3762: 700: 6293: 6230: 6169: 6100: 5990: 5772: 5648: 5605: 5562: 5519: 5436: 5353: 5310: 5267: 5224: 5181: 5113: 4946: 4791: 4748: 4705: 4568: 4545: 4502: 4459: 4416: 4266: 4101: 4038: 3390: 3144: 2795: 2024: 1871: 1829: 1778: 1683: 1634: 1585: 1534: 1484: 1434: 1263: 974: 382: 233: 6987: 6270: 6250: 6120: 6077: 6057: 6037: 6013: 5967: 5866: 5846: 5819: 5795: 5749: 5703: 5668: 5625: 5582: 5539: 5496: 5476: 5456: 5413: 5393: 5373: 5330: 5287: 5244: 5201: 5158: 5138: 5020: 5000: 4970: 4923: 4903: 4883: 4863: 4811: 4768: 4725: 4682: 4628: 4608: 4588: 4522: 4479: 4436: 4393: 4326: 4306: 4286: 4176: 4121: 4078: 4058: 4015: 3729: 3657: 3637: 3617: 3542: 3522: 3410: 3209: 3085: 3065: 2901: 2768: 2641: 2621: 2598: 2533: 2415: 2395: 2334: 2287: 2255: 2128: 2108: 2001: 1798: 1725: 1705: 1654: 1607: 1554: 1511: 1457: 1371: 1313: 1240: 1220: 1140: 1113: 1093: 1073: 1049: 1014: 994: 948: 628: 597: 577: 557: 537: 513: 402: 359: 339: 319: 210: 190: 170: 150: 126: 106: 86: 63: 732: 2950: 3284:
If no element occurs infinitely many times in the sequence, for example if all the elements are distinct, any accumulation point of the sequence is an
6431: 3524:
is an accumulation point of any of the corresponding sequences (because any neighborhood of the point will contain infinitely many elements of
6564: 6526: 6496: 6621: 2820: 1917: 6975: 6970: 6488: 6476: 6965: 3997:
We use the fact that a point is in the closure of a set if and only if every neighborhood of the point meets the set. Now,
3149: 6867: 6592: 2266: 1316: 3442: 6587: 3307: 3247: 3090: 2601: 2572: 1981: 1052: 129: 3214: 2906: 785: 774: 6875: 7018: 6328: 2798: 1845: 1460: 453: 253: 3672:
of a non-constant sequence is an accumulation point of the sequence. And by definition, every limit point is an
6946: 6674: 6483: 6960: 3682: 2802: 2133: 458: 6895: 6890: 6816: 6693: 6681: 6654: 6614: 6582: 6552: 2562: 24: 6435: 6737: 6664: 2262: 1324: 6925: 4181: 4126: 3959: 2435: 2029: 6180: 1380: 6885: 6837: 6811: 6659: 3891:{\displaystyle \operatorname {cl} (S)=L(S)\cup I(S)\quad {\text{and}}\quad L(S)\cap I(S)=\emptyset .} 3619:
cannot be an accumulation point of any of the associated sequences without infinite repeats (because
2771: 462: 7008: 6936: 6732: 6358: 6352: 6346: 6334: 3669: 2945: 2806: 2374: 2339: 1410: 851: 768: 760: 466: 445: 20: 6125: 5025: 3929: 3415: 3346: 2292: 862: 737: 659: 6930: 6880: 6801: 6791: 6669: 6649: 6556: 6310: 5848:
is discrete, then every point is isolated and cannot be a limit point of any set. Conversely, if
4365: 3953: 2797:
Cluster points in nets encompass the idea of both condensation points and ω-accumulation points.
2682: 2646: 2204: 2171: 2057: 1658: 491: 407: 6900: 2715: 5355:
However, a set can not have a non-trivial intersection with its complement. Conversely, assume
2482: 7013: 6918: 6784: 6742: 6607: 6570: 6560: 6532: 6522: 6502: 6492: 6337: â€“ Use of filters to describe and characterize all basic topological notions and results. 6322: â€“ Use of filters to describe and characterize all basic topological notions and results. 6319: 5923: 2425: 1841: 951: 779: 679: 470: 441: 299: 66: 43: 3582: 3487: 3287: 2417:
contains all but finitely many elements of the sequence). That is why we do not use the term
1734: 756:
with standard topology (for a less trivial example of a limit point, see the first caption).
6698: 6644: 6472: 6016: 3903: 3552: 3024: 2538: 1876: 1330: 1179: 5897: 5871: 5708: 4816: 4633: 4331: 1268: 1146: 633: 6757: 6752: 5066: 4219: 3767: 3738: 1610: 919: 685: 6275: 6212: 6151: 6082: 5972: 5754: 5630: 5587: 5544: 5501: 5418: 5335: 5292: 5249: 5206: 5163: 5095: 4928: 4773: 4730: 4687: 4550: 4527: 4484: 4441: 4398: 4248: 4083: 4020: 3372: 3126: 2777: 2006: 1853: 1811: 1760: 1665: 1616: 1567: 1516: 1466: 1416: 1245: 956: 859:
here), viz. -1 and +1. Thus, thinking of sets, these points are limit points of the set
364: 215: 6847: 6779: 6514: 6340: 6304: 6255: 6235: 6105: 6062: 6042: 6022: 5998: 5952: 5851: 5831: 5804: 5798: 5780: 5734: 5688: 5675: 5653: 5610: 5567: 5524: 5481: 5461: 5441: 5398: 5378: 5358: 5315: 5272: 5229: 5186: 5143: 5123: 5005: 4985: 4955: 4908: 4888: 4868: 4848: 4796: 4753: 4710: 4667: 4613: 4593: 4573: 4507: 4464: 4421: 4378: 4311: 4291: 4271: 4161: 4106: 4063: 4043: 4000: 3732: 3714: 3673: 3642: 3622: 3602: 3527: 3507: 3395: 3194: 3070: 3050: 3010:{\displaystyle \operatorname {Im} x_{\bullet }:=\left\{x_{n}:n\in \mathbb {N} \right\}} 2886: 2753: 2626: 2606: 2583: 2518: 2400: 2380: 2319: 2272: 2240: 2113: 2093: 1986: 1783: 1710: 1690: 1639: 1592: 1539: 1496: 1442: 1356: 1298: 1225: 1205: 1125: 1098: 1078: 1058: 1034: 999: 979: 933: 613: 607: 600: 582: 562: 542: 522: 498: 485: 474: 387: 344: 324: 304: 195: 175: 155: 135: 111: 91: 71: 48: 5627:
can be expressed as a union of open neighbourhoods of the points in the complement of
705: 7002: 6857: 6767: 6747: 6544: 6307: â€“ Point that belongs to the closure of some given subset of a topological space 6950: 6842: 6762: 6708: 3639:
has a neighborhood that contains only finitely many (possibly even none) points of
2512: 2258: 1320: 1173: 2813:
Relation between accumulation point of a sequence and accumulation point of a set
6940: 6852: 1728: 923: 914: 855:(i.e. does not converge), but has two accumulation points (which are considered 440:
This definition of a cluster or accumulation point of a sequence generalizes to
599:
itself. A limit point can be characterized as an adherent point that is not an
19:"Limit point" redirects here. For uses where the word "point" is optional, see 6796: 6727: 6686: 3659:
and that neighborhood can only contain finitely many terms of such sequences).
764: 6536: 4952:
A corollary of this result gives us a characterisation of closed sets: A set
6821: 6574: 6506: 2367: 6403: 3412:
in many ways, even with repeats, and thus associate with it many sequences
6417: 6806: 6774: 6723: 6630: 2429: 1374: 1143: 248: 236: 6343: â€“ Point of a subset S around which there are no other points of S 5375:
contains all its limit points. We shall show that the complement of
2366:
The set of all cluster points of a sequence is sometimes called the
1436:
In fact, Fréchet–Urysohn spaces are characterized by this property.
5458:
is not a limit point, and hence there exists an open neighbourhood
2421:
of a sequence as a synonym for accumulation point of the sequence.
913: 3544:
and hence also infinitely many terms in any associated sequence).
3123:
For example, if the sequence is the constant sequence with value
2397:
to which the sequence converges (that is, every neighborhood of
6603: 2876:{\displaystyle x_{\bullet }=\left(x_{n}\right)_{n=1}^{\infty }} 1973:{\displaystyle x_{\bullet }=\left(x_{n}\right)_{n=1}^{\infty }} 4972:
is closed if and only if it contains all of its limit points.
4268:
then we have the following characterization of the closure of
481:
synonymous with "cluster/accumulation point of a sequence".
6599: 3087:
need not be an accumulation point of the corresponding set
702:
is a limit point (though not a boundary point) of interval
6491:. Berlin New York: Springer Science & Business Media. 579:
may have a neighbourhood not containing points other than
6324:
Pages displaying short descriptions of redirect targets
630:
is a boundary point (but not a limit point) of the set
606:
Limit points of a set should also not be confused with
484:
The limit points of a set should not be confused with
6404:"Difference between boundary point & limit point" 6349: â€“ Point to which functions converge in analysis 6278: 6258: 6238: 6215: 6183: 6154: 6128: 6108: 6085: 6065: 6045: 6025: 6001: 5975: 5955: 5926: 5900: 5894:
that is not open. Hence, every open neighbourhood of
5874: 5854: 5834: 5807: 5783: 5757: 5737: 5711: 5691: 5656: 5633: 5613: 5590: 5570: 5547: 5527: 5504: 5484: 5464: 5444: 5421: 5401: 5381: 5361: 5338: 5318: 5295: 5275: 5252: 5232: 5209: 5189: 5166: 5146: 5126: 5098: 5069: 5028: 5008: 4988: 4958: 4931: 4911: 4891: 4871: 4851: 4819: 4799: 4776: 4756: 4733: 4713: 4690: 4670: 4636: 4616: 4596: 4576: 4553: 4530: 4510: 4487: 4467: 4444: 4424: 4401: 4381: 4334: 4314: 4294: 4274: 4251: 4222: 4184: 4164: 4129: 4109: 4086: 4066: 4046: 4023: 4003: 3962: 3932: 3906: 3799: 3770: 3741: 3717: 3685: 3645: 3625: 3605: 3585: 3555: 3530: 3510: 3490: 3445: 3418: 3398: 3375: 3349: 3310: 3290: 3250: 3217: 3197: 3184:{\displaystyle \operatorname {Im} x_{\bullet }=\{x\}} 3152: 3129: 3093: 3073: 3053: 3027: 2953: 2909: 2889: 2823: 2780: 2756: 2718: 2685: 2649: 2629: 2609: 2586: 2541: 2521: 2485: 2438: 2403: 2383: 2342: 2322: 2295: 2275: 2243: 2207: 2174: 2136: 2116: 2096: 2090:
It is equivalent to say that for every neighbourhood
2060: 2032: 2009: 1989: 1920: 1879: 1856: 1814: 1786: 1763: 1737: 1713: 1693: 1668: 1642: 1619: 1595: 1570: 1542: 1519: 1499: 1469: 1445: 1419: 1383: 1359: 1333: 1301: 1271: 1248: 1228: 1208: 1182: 1149: 1128: 1101: 1081: 1061: 1037: 1002: 982: 959: 936: 865: 788: 740: 708: 688: 662: 636: 616: 585: 565: 545: 525: 501: 410: 390: 367: 347: 327: 307: 256: 218: 198: 178: 158: 138: 114: 94: 74: 51: 6315:
Pages displaying wikidata descriptions as a fallback
759:
This concept profitably generalizes the notion of a
6866: 6830: 6716: 6637: 3047:that occurs infinitely many times in the sequence, 6287: 6264: 6244: 6224: 6201: 6163: 6140: 6114: 6094: 6071: 6051: 6031: 6007: 5984: 5961: 5941: 5912: 5886: 5860: 5840: 5813: 5789: 5766: 5743: 5723: 5697: 5662: 5642: 5619: 5599: 5576: 5556: 5533: 5513: 5490: 5470: 5450: 5430: 5407: 5387: 5367: 5347: 5324: 5304: 5281: 5261: 5238: 5218: 5195: 5175: 5152: 5132: 5107: 5084: 5055: 5014: 4994: 4964: 4940: 4917: 4897: 4877: 4857: 4837: 4805: 4785: 4762: 4742: 4719: 4699: 4676: 4654: 4622: 4602: 4582: 4562: 4539: 4516: 4496: 4473: 4453: 4430: 4410: 4387: 4352: 4320: 4300: 4280: 4260: 4237: 4205: 4170: 4150: 4115: 4095: 4072: 4052: 4032: 4009: 3983: 3944: 3918: 3890: 3785: 3756: 3723: 3703: 3651: 3631: 3611: 3591: 3567: 3536: 3516: 3496: 3474:{\displaystyle A=\operatorname {Im} x_{\bullet }.} 3473: 3431: 3404: 3384: 3361: 3332: 3296: 3272: 3236: 3203: 3183: 3138: 3115: 3079: 3059: 3039: 3009: 2936: 2895: 2875: 2789: 2762: 2742: 2704: 2671: 2635: 2615: 2592: 2553: 2527: 2503: 2471: 2409: 2389: 2358: 2328: 2308: 2281: 2249: 2229: 2193: 2160: 2122: 2102: 2082: 2046: 2018: 1995: 1972: 1891: 1865: 1823: 1792: 1772: 1749: 1719: 1699: 1677: 1648: 1628: 1601: 1579: 1548: 1528: 1505: 1478: 1451: 1428: 1401: 1365: 1345: 1307: 1284: 1257: 1234: 1214: 1194: 1162: 1134: 1107: 1087: 1067: 1043: 1008: 988: 968: 942: 893: 841: 748: 726: 694: 670: 648: 622: 591: 571: 551: 531: 507: 432: 396: 376: 353: 333: 313: 290: 227: 204: 184: 164: 144: 120: 100: 80: 57: 6355: â€“ Value to which tends an infinite sequence 6059:with more than one element, then all elements of 3333:{\displaystyle \operatorname {Im} x_{\bullet }.} 3273:{\displaystyle \operatorname {Im} x_{\bullet }.} 3116:{\displaystyle \operatorname {Im} x_{\bullet }.} 3237:{\displaystyle \operatorname {Im} x_{\bullet }} 1842:Net (mathematics) § Cluster point of a net 3067:is an accumulation point of the sequence. But 2937:{\displaystyle x_{\bullet }:\mathbb {N} \to X} 842:{\displaystyle x_{n}=(-1)^{n}{\frac {n}{n+1}}} 6615: 539:. Unlike for limit points, an adherent point 8: 6196: 6190: 5907: 5901: 5881: 5875: 5718: 5712: 5332:should have a non-trivial intersection with 4197: 4191: 4142: 4136: 3975: 3969: 3178: 3172: 1556:is a specific type of limit point called an 1489:Special types of accumulation point of a set 1396: 1390: 1292:spaces are characterized by this property. 885: 872: 763:and is the underpinning of concepts such as 643: 637: 235:There is also a closely related concept for 5868:is not discrete, then there is a singleton 3343:Conversely, given a countable infinite set 1800:is a specific type of limit point called a 1656:is a specific type of limit point called a 465:) by definition refers to a point that the 291:{\displaystyle (x_{n})_{n\in \mathbb {N} }} 6983: 6956: 6622: 6608: 6600: 3304:-accumulation point of the associated set 384:there are infinitely many natural numbers 6277: 6257: 6237: 6214: 6182: 6153: 6127: 6107: 6084: 6064: 6044: 6024: 6000: 5974: 5954: 5925: 5899: 5873: 5853: 5833: 5806: 5782: 5756: 5736: 5710: 5690: 5655: 5632: 5612: 5589: 5569: 5546: 5526: 5503: 5483: 5463: 5443: 5420: 5400: 5380: 5360: 5337: 5317: 5294: 5274: 5251: 5231: 5208: 5188: 5165: 5145: 5125: 5097: 5068: 5027: 5007: 4987: 4957: 4930: 4910: 4890: 4870: 4850: 4818: 4798: 4775: 4755: 4732: 4712: 4689: 4669: 4635: 4615: 4595: 4575: 4552: 4529: 4509: 4486: 4466: 4443: 4423: 4400: 4380: 4333: 4313: 4293: 4273: 4250: 4221: 4183: 4163: 4128: 4108: 4085: 4065: 4045: 4022: 4002: 3961: 3931: 3905: 3846: 3798: 3769: 3740: 3716: 3684: 3644: 3624: 3604: 3584: 3554: 3529: 3509: 3489: 3462: 3444: 3423: 3417: 3397: 3374: 3348: 3321: 3309: 3289: 3261: 3249: 3228: 3216: 3196: 3163: 3151: 3128: 3104: 3092: 3072: 3052: 3026: 2998: 2997: 2982: 2964: 2952: 2924: 2923: 2914: 2908: 2888: 2867: 2856: 2846: 2828: 2822: 2779: 2755: 2717: 2696: 2684: 2654: 2648: 2628: 2608: 2585: 2540: 2520: 2484: 2437: 2402: 2382: 2373:Note that there is already the notion of 2347: 2341: 2321: 2300: 2294: 2274: 2242: 2212: 2206: 2185: 2173: 2151: 2150: 2141: 2135: 2115: 2095: 2065: 2059: 2040: 2039: 2031: 2008: 1988: 1964: 1953: 1943: 1925: 1919: 1878: 1855: 1834:Accumulation points of sequences and nets 1813: 1785: 1762: 1736: 1712: 1692: 1667: 1641: 1618: 1594: 1569: 1541: 1518: 1498: 1468: 1444: 1418: 1382: 1358: 1332: 1300: 1276: 1270: 1247: 1227: 1207: 1181: 1154: 1148: 1127: 1100: 1080: 1060: 1036: 1001: 981: 958: 935: 879: 864: 821: 815: 793: 787: 742: 741: 739: 707: 687: 664: 663: 661: 635: 615: 584: 564: 544: 524: 500: 415: 409: 389: 366: 346: 326: 306: 282: 281: 274: 264: 255: 217: 212:does not itself have to be an element of 197: 177: 157: 137: 113: 93: 73: 50: 25:Limit (disambiguation) § Mathematics 6390: 6378: 6331: â€“ Set of all limit points of a set 6313: â€“ a stronger analog of limit point 5564:Since this argument holds for arbitrary 773: 108:that can be "approximated" by points of 6455: 6371: 6187: 6132: 5022:is equal to its closure if and only if 4188: 4133: 3966: 1387: 3704:{\displaystyle \operatorname {cl} (S)} 2161:{\displaystyle n_{0}\in \mathbb {N} ,} 1222:if and only if every neighbourhood of 6361: â€“ The limit of some subsequence 4245:to denote the set of limit points of 4103:if and only if every neighborhood of 4040:if and only if every neighborhood of 3392:we can enumerate all the elements of 7: 6122:is a singleton, then every point of 4360:This fact is sometimes taken as the 918:A sequence enumerating all positive 16:Cluster point in a topological space 5751:that contains no points other than 5541:lies entirely in the complement of 5246:comprises an open neighbourhood of 1513:contains infinitely many points of 1242:contains infinitely many points of 782:, the sequence of rational numbers 495:) for which every neighbourhood of 341:such that, for every neighbourhood 3882: 3017:can be defined in the usual way. 2868: 2336:is a limit of some subsequence of 1965: 14: 6432:"Examples of Accumulation Points" 6209:is nonempty, its closure will be 4206:{\displaystyle S\setminus \{x\}.} 4151:{\displaystyle S\setminus \{x\},} 3984:{\displaystyle S\setminus \{x\}.} 3244:and not an accumulation point of 2472:{\displaystyle f:(P,\leq )\to X,} 2047:{\displaystyle n\in \mathbb {N} } 6982: 6955: 6945: 6935: 6924: 6914: 6913: 6707: 6202:{\displaystyle S\setminus \{x\}} 5415:be a point in the complement of 2535:is a topological space. A point 1911:accumulation point of a sequence 1402:{\displaystyle S\setminus \{x\}} 451:The similarly named notion of a 3851: 3845: 1075:contains at least one point of 192:itself. A limit point of a set 6478:General Topology: Chapters 1–4 5079: 5073: 5050: 5044: 4829: 4823: 4646: 4640: 4344: 4338: 4232: 4226: 3876: 3870: 3861: 3855: 3842: 3836: 3827: 3821: 3812: 3806: 3780: 3774: 3751: 3745: 3698: 3692: 2928: 2728: 2722: 2498: 2486: 2460: 2457: 2445: 812: 802: 721: 709: 271: 257: 1: 5678:is a limit point of any set. 2359:{\displaystyle x_{\bullet }.} 1028:accumulation point of the set 6434:. 2021-01-13. Archived from 6141:{\displaystyle X\setminus S} 5801:if and only if no subset of 5056:{\displaystyle S=S\cup L(S)} 4845:then every neighbourhood of 4707:then every neighbourhood of 4504:then every neighbourhood of 3952:if and only if it is in the 3945:{\displaystyle S\subseteq X} 3432:{\displaystyle x_{\bullet }} 3362:{\displaystyle A\subseteq X} 2903:is by definition just a map 2309:{\displaystyle x_{\bullet }} 910:Accumulation points of a set 894:{\displaystyle S=\{x_{n}\}.} 749:{\displaystyle \mathbb {R} } 671:{\displaystyle \mathbb {R} } 6588:Encyclopedia of Mathematics 6521:. Boston: Allyn and Bacon. 5705:is an isolated point, then 4925:is again in the closure of 3021:If there exists an element 2705:{\displaystyle p\geq p_{0}} 2672:{\displaystyle p_{0}\in P,} 2576:accumulation point of a net 2230:{\displaystyle x_{n}\in V.} 2194:{\displaystyle n\geq n_{0}} 2083:{\displaystyle x_{n}\in V.} 1804:complete accumulation point 1439:The set of limit points of 433:{\displaystyle x_{n}\in V.} 7035: 6876:Banach fixed-point theorem 5312:any open neighbourhood of 4948:This completes the proof. 2743:{\displaystyle f(p)\in V,} 2428:generalizes the idea of a 2026:there are infinitely many 1839: 1757:equals the cardinality of 1589:If every neighbourhood of 1493:If every neighbourhood of 1373:if and only if there is a 778:With respect to the usual 18: 6909: 6705: 6329:Derived set (mathematics) 6272:is the unique element of 5002:is closed if and only if 4547:and this point cannot be 4308:is equal to the union of 2504:{\displaystyle (P,\leq )} 1846:Cluster point of a filter 454:limit point of a sequence 6489:ÉlĂ©ments de mathĂ©matique 5942:{\displaystyle y\neq x,} 5650:Hence the complement of 5498:that does not intersect 4375:("Left subset") Suppose 3211:is an isolated point of 128:in the sense that every 6418:"What is a limit point" 5226:then the complement to 3599:-accumulation point of 3592:{\displaystyle \omega } 3504:-accumulation point of 3497:{\displaystyle \omega } 3297:{\displaystyle \omega } 2265:(or, more generally, a 1850:In a topological space 1750:{\displaystyle U\cap S} 1687:If every neighbourhood 459:limit point of a filter 6931:Mathematics portal 6831:Metrics and properties 6817:Second-countable space 6583:"Limit point of a set" 6553:Upper Saddle River, NJ 6289: 6266: 6246: 6232:It is only empty when 6226: 6203: 6165: 6142: 6116: 6096: 6073: 6053: 6033: 6009: 5986: 5963: 5943: 5914: 5888: 5862: 5842: 5815: 5791: 5768: 5745: 5731:is a neighbourhood of 5725: 5699: 5664: 5644: 5621: 5601: 5578: 5558: 5535: 5515: 5492: 5472: 5452: 5432: 5409: 5389: 5369: 5349: 5326: 5306: 5283: 5263: 5240: 5220: 5197: 5177: 5154: 5134: 5109: 5086: 5057: 5016: 4996: 4966: 4942: 4919: 4899: 4879: 4859: 4839: 4807: 4787: 4764: 4744: 4721: 4701: 4678: 4656: 4624: 4604: 4584: 4564: 4541: 4518: 4498: 4475: 4455: 4432: 4412: 4389: 4354: 4322: 4302: 4282: 4262: 4239: 4207: 4172: 4152: 4117: 4097: 4074: 4054: 4034: 4011: 3985: 3946: 3920: 3919:{\displaystyle x\in X} 3892: 3787: 3758: 3725: 3705: 3653: 3633: 3613: 3593: 3569: 3568:{\displaystyle x\in X} 3538: 3518: 3498: 3475: 3433: 3406: 3386: 3363: 3334: 3298: 3274: 3238: 3205: 3185: 3140: 3117: 3081: 3061: 3041: 3040:{\displaystyle x\in X} 3011: 2938: 2897: 2877: 2791: 2764: 2744: 2706: 2673: 2637: 2617: 2594: 2555: 2554:{\displaystyle x\in X} 2529: 2505: 2473: 2432:. A net is a function 2411: 2391: 2360: 2330: 2310: 2289:is a cluster point of 2283: 2251: 2231: 2195: 2162: 2124: 2104: 2084: 2048: 2020: 1997: 1974: 1893: 1892:{\displaystyle x\in X} 1867: 1825: 1794: 1774: 1751: 1721: 1701: 1679: 1650: 1630: 1603: 1581: 1550: 1530: 1507: 1480: 1453: 1430: 1403: 1367: 1347: 1346:{\displaystyle x\in X} 1325:first-countable spaces 1309: 1286: 1259: 1236: 1216: 1196: 1195:{\displaystyle x\in X} 1164: 1136: 1109: 1089: 1069: 1045: 1010: 990: 970: 944: 927: 901: 895: 843: 750: 728: 696: 672: 650: 624: 593: 573: 553: 533: 509: 434: 398: 378: 355: 335: 315: 292: 229: 206: 186: 166: 146: 122: 102: 82: 59: 6290: 6267: 6247: 6227: 6204: 6166: 6143: 6117: 6097: 6074: 6054: 6034: 6010: 5987: 5964: 5944: 5915: 5913:{\displaystyle \{x\}} 5889: 5887:{\displaystyle \{x\}} 5863: 5843: 5816: 5792: 5769: 5746: 5726: 5724:{\displaystyle \{x\}} 5700: 5665: 5645: 5622: 5602: 5584:in the complement of 5579: 5559: 5536: 5516: 5493: 5473: 5453: 5433: 5410: 5390: 5370: 5350: 5327: 5307: 5284: 5264: 5241: 5221: 5198: 5178: 5155: 5135: 5110: 5087: 5058: 5017: 4997: 4967: 4943: 4920: 4900: 4880: 4860: 4840: 4838:{\displaystyle L(S),} 4808: 4788: 4770:is in the closure of 4765: 4745: 4722: 4702: 4679: 4657: 4655:{\displaystyle L(S).} 4625: 4605: 4585: 4565: 4542: 4519: 4499: 4476: 4456: 4433: 4413: 4395:is in the closure of 4390: 4355: 4353:{\displaystyle L(S).} 4323: 4303: 4283: 4263: 4240: 4208: 4178:is in the closure of 4173: 4153: 4118: 4098: 4075: 4055: 4035: 4012: 3986: 3947: 3921: 3893: 3788: 3759: 3726: 3706: 3654: 3634: 3614: 3594: 3570: 3539: 3519: 3499: 3476: 3434: 3407: 3387: 3364: 3335: 3299: 3275: 3239: 3206: 3186: 3141: 3118: 3082: 3062: 3042: 3012: 2939: 2898: 2878: 2805:are also defined for 2792: 2765: 2745: 2707: 2674: 2638: 2618: 2595: 2556: 2530: 2506: 2474: 2412: 2392: 2361: 2331: 2311: 2284: 2267:FrĂ©chet–Urysohn space 2263:first-countable space 2252: 2232: 2196: 2163: 2125: 2105: 2085: 2049: 2021: 1998: 1975: 1894: 1868: 1826: 1795: 1775: 1752: 1722: 1702: 1680: 1651: 1631: 1604: 1582: 1551: 1531: 1508: 1481: 1454: 1431: 1404: 1368: 1348: 1317:FrĂ©chet–Urysohn space 1310: 1287: 1285:{\displaystyle T_{1}} 1260: 1237: 1217: 1197: 1165: 1163:{\displaystyle T_{1}} 1137: 1110: 1090: 1070: 1046: 1011: 991: 971: 945: 917: 896: 844: 777: 751: 729: 697: 673: 651: 649:{\displaystyle \{0\}} 625: 594: 574: 554: 534: 510: 467:sequence converges to 435: 399: 379: 356: 336: 316: 293: 230: 207: 187: 167: 147: 123: 103: 83: 60: 6886:Invariance of domain 6838:Euler characteristic 6812:Bundle (mathematics) 6276: 6256: 6236: 6213: 6181: 6152: 6148:is a limit point of 6126: 6106: 6083: 6079:are limit points of 6063: 6043: 6023: 5999: 5973: 5969:is a limit point of 5953: 5924: 5898: 5872: 5852: 5832: 5805: 5781: 5755: 5735: 5709: 5689: 5654: 5631: 5611: 5588: 5568: 5545: 5525: 5502: 5482: 5462: 5442: 5419: 5399: 5395:is an open set. Let 5379: 5359: 5336: 5316: 5293: 5289:is a limit point of 5273: 5250: 5230: 5207: 5187: 5164: 5144: 5140:be a closed set and 5124: 5096: 5085:{\displaystyle L(S)} 5067: 5026: 5006: 4986: 4956: 4929: 4909: 4889: 4869: 4865:contains a point of 4849: 4817: 4797: 4774: 4754: 4731: 4711: 4688: 4668: 4664:("Right subset") If 4634: 4614: 4594: 4590:is a limit point of 4574: 4551: 4528: 4524:contains a point of 4508: 4485: 4465: 4442: 4422: 4399: 4379: 4332: 4312: 4292: 4272: 4249: 4238:{\displaystyle L(S)} 4220: 4182: 4162: 4127: 4123:contains a point of 4107: 4084: 4064: 4060:contains a point of 4044: 4021: 4017:is a limit point of 4001: 3960: 3930: 3926:is a limit point of 3904: 3797: 3786:{\displaystyle I(S)} 3768: 3764:and isolated points 3757:{\displaystyle L(S)} 3739: 3735:of its limit points 3715: 3683: 3643: 3623: 3603: 3583: 3553: 3528: 3508: 3488: 3443: 3416: 3396: 3373: 3347: 3308: 3288: 3248: 3215: 3195: 3150: 3127: 3091: 3071: 3051: 3025: 2951: 2907: 2887: 2821: 2778: 2754: 2716: 2683: 2647: 2627: 2607: 2584: 2539: 2519: 2483: 2436: 2401: 2381: 2340: 2320: 2293: 2273: 2241: 2205: 2172: 2134: 2114: 2094: 2058: 2030: 2007: 1987: 1918: 1877: 1854: 1812: 1784: 1761: 1735: 1711: 1691: 1666: 1640: 1617: 1593: 1568: 1560:ω-accumulation point 1540: 1517: 1497: 1467: 1443: 1417: 1381: 1357: 1353:is a limit point of 1331: 1299: 1269: 1246: 1226: 1206: 1202:is a limit point of 1180: 1147: 1126: 1099: 1079: 1059: 1035: 1000: 980: 957: 934: 863: 786: 738: 706: 686: 660: 634: 614: 583: 563: 543: 523: 499: 463:limit point of a net 408: 388: 365: 345: 325: 305: 254: 216: 196: 176: 156: 152:contains a point of 136: 112: 92: 72: 49: 6896:Tychonoff's theorem 6891:PoincarĂ© conjecture 6645:General (point-set) 6551:(Second ed.). 6381:, pp. 209–210. 6359:Subsequential limit 6353:Limit of a sequence 6347:Limit of a function 6335:Filters in topology 5821:has a limit point. 2872: 2774:which converges to 2375:limit of a sequence 1969: 926:is a cluster point. 769:topological closure 695:{\displaystyle 0.5} 471:filter converges to 469:(respectively, the 21:Limit (mathematics) 6881:De Rham cohomology 6802:Polyhedral complex 6792:Simplicial complex 6557:Prentice Hall, Inc 6484:Topologie GĂ©nĂ©rale 6458:, pp. 97–102. 6311:Condensation point 6288:{\displaystyle S.} 6285: 6262: 6242: 6225:{\displaystyle X.} 6222: 6199: 6175: 6164:{\displaystyle S.} 6161: 6138: 6112: 6095:{\displaystyle S.} 6092: 6069: 6049: 6029: 6005: 5985:{\displaystyle X.} 5982: 5959: 5939: 5910: 5884: 5858: 5838: 5826: 5811: 5787: 5767:{\displaystyle x.} 5764: 5741: 5721: 5695: 5683: 5660: 5643:{\displaystyle S.} 5640: 5617: 5607:the complement of 5600:{\displaystyle S,} 5597: 5574: 5557:{\displaystyle S.} 5554: 5531: 5514:{\displaystyle S,} 5511: 5488: 5468: 5448: 5431:{\displaystyle S.} 5428: 5405: 5385: 5365: 5348:{\displaystyle S.} 5345: 5322: 5305:{\displaystyle S,} 5302: 5279: 5262:{\displaystyle x.} 5259: 5236: 5219:{\displaystyle S,} 5216: 5193: 5176:{\displaystyle S.} 5173: 5150: 5130: 5108:{\displaystyle S.} 5105: 5082: 5053: 5012: 4992: 4977: 4962: 4941:{\displaystyle S.} 4938: 4915: 4895: 4875: 4855: 4835: 4803: 4786:{\displaystyle S.} 4783: 4760: 4743:{\displaystyle S,} 4740: 4717: 4700:{\displaystyle S,} 4697: 4674: 4652: 4620: 4600: 4580: 4563:{\displaystyle x.} 4560: 4540:{\displaystyle S,} 4537: 4514: 4497:{\displaystyle S,} 4494: 4471: 4454:{\displaystyle S,} 4451: 4428: 4411:{\displaystyle S.} 4408: 4385: 4373: 4350: 4318: 4298: 4278: 4261:{\displaystyle S,} 4258: 4235: 4203: 4168: 4148: 4113: 4096:{\displaystyle x,} 4093: 4070: 4050: 4033:{\displaystyle S,} 4030: 4007: 3995: 3981: 3942: 3916: 3888: 3783: 3754: 3721: 3701: 3649: 3629: 3609: 3589: 3565: 3534: 3514: 3494: 3471: 3439:that will satisfy 3429: 3402: 3385:{\displaystyle X,} 3382: 3359: 3330: 3294: 3270: 3234: 3201: 3181: 3139:{\displaystyle x,} 3136: 3113: 3077: 3057: 3037: 3007: 2934: 2893: 2873: 2837: 2790:{\displaystyle x.} 2787: 2760: 2740: 2702: 2669: 2633: 2613: 2590: 2551: 2525: 2501: 2469: 2407: 2387: 2356: 2326: 2306: 2279: 2247: 2227: 2191: 2158: 2120: 2100: 2080: 2044: 2019:{\displaystyle x,} 2016: 1993: 1970: 1934: 1889: 1866:{\displaystyle X,} 1863: 1824:{\displaystyle S.} 1821: 1790: 1773:{\displaystyle S,} 1770: 1747: 1717: 1697: 1678:{\displaystyle S.} 1675: 1659:condensation point 1646: 1629:{\displaystyle S,} 1626: 1599: 1580:{\displaystyle S.} 1577: 1546: 1529:{\displaystyle S,} 1526: 1503: 1479:{\displaystyle S.} 1476: 1449: 1429:{\displaystyle x.} 1426: 1399: 1363: 1343: 1305: 1282: 1258:{\displaystyle S.} 1255: 1232: 1212: 1192: 1160: 1132: 1105: 1085: 1065: 1041: 1006: 986: 969:{\displaystyle X.} 966: 940: 928: 902: 891: 839: 780:Euclidean topology 746: 724: 692: 668: 646: 620: 589: 569: 549: 529: 505: 430: 394: 377:{\displaystyle x,} 374: 351: 331: 311: 288: 245:accumulation point 228:{\displaystyle S.} 225: 202: 182: 162: 142: 118: 98: 78: 55: 36:accumulation point 30:In mathematics, a 6996: 6995: 6785:fundamental group 6566:978-0-13-181629-9 6545:Munkres, James R. 6528:978-0-697-06889-7 6498:978-3-540-64241-1 6473:Bourbaki, Nicolas 6393:, pp. 68–83. 6320:Convergent filter 6265:{\displaystyle x} 6245:{\displaystyle S} 6173: 6115:{\displaystyle S} 6072:{\displaystyle X} 6052:{\displaystyle X} 6032:{\displaystyle S} 6008:{\displaystyle X} 5962:{\displaystyle x} 5920:contains a point 5861:{\displaystyle X} 5841:{\displaystyle X} 5824: 5814:{\displaystyle X} 5790:{\displaystyle X} 5744:{\displaystyle x} 5698:{\displaystyle x} 5681: 5663:{\displaystyle S} 5620:{\displaystyle S} 5577:{\displaystyle x} 5534:{\displaystyle U} 5491:{\displaystyle x} 5471:{\displaystyle U} 5451:{\displaystyle x} 5408:{\displaystyle x} 5388:{\displaystyle S} 5368:{\displaystyle S} 5325:{\displaystyle x} 5282:{\displaystyle x} 5239:{\displaystyle S} 5196:{\displaystyle x} 5160:a limit point of 5153:{\displaystyle x} 5133:{\displaystyle S} 5015:{\displaystyle S} 4995:{\displaystyle S} 4975: 4965:{\displaystyle S} 4918:{\displaystyle x} 4898:{\displaystyle x} 4878:{\displaystyle S} 4858:{\displaystyle x} 4806:{\displaystyle x} 4763:{\displaystyle x} 4720:{\displaystyle x} 4677:{\displaystyle x} 4623:{\displaystyle x} 4603:{\displaystyle S} 4583:{\displaystyle x} 4517:{\displaystyle x} 4474:{\displaystyle x} 4431:{\displaystyle x} 4388:{\displaystyle x} 4371: 4321:{\displaystyle S} 4301:{\displaystyle S} 4288:: The closure of 4281:{\displaystyle S} 4171:{\displaystyle x} 4116:{\displaystyle x} 4073:{\displaystyle S} 4053:{\displaystyle x} 4010:{\displaystyle x} 3993: 3849: 3724:{\displaystyle S} 3652:{\displaystyle A} 3632:{\displaystyle x} 3612:{\displaystyle A} 3537:{\displaystyle A} 3517:{\displaystyle A} 3405:{\displaystyle A} 3204:{\displaystyle x} 3080:{\displaystyle x} 3060:{\displaystyle x} 2896:{\displaystyle X} 2763:{\displaystyle f} 2750:equivalently, if 2636:{\displaystyle x} 2616:{\displaystyle V} 2593:{\displaystyle f} 2528:{\displaystyle X} 2424:The concept of a 2410:{\displaystyle x} 2390:{\displaystyle x} 2329:{\displaystyle x} 2282:{\displaystyle x} 2250:{\displaystyle X} 2123:{\displaystyle x} 2103:{\displaystyle V} 1996:{\displaystyle V} 1793:{\displaystyle x} 1727:is such that the 1720:{\displaystyle x} 1700:{\displaystyle U} 1649:{\displaystyle x} 1602:{\displaystyle x} 1549:{\displaystyle x} 1506:{\displaystyle x} 1452:{\displaystyle S} 1366:{\displaystyle S} 1308:{\displaystyle X} 1235:{\displaystyle x} 1215:{\displaystyle S} 1135:{\displaystyle X} 1108:{\displaystyle x} 1088:{\displaystyle S} 1068:{\displaystyle x} 1044:{\displaystyle S} 1009:{\displaystyle X} 989:{\displaystyle x} 952:topological space 950:be a subset of a 943:{\displaystyle S} 837: 680:standard topology 623:{\displaystyle 0} 592:{\displaystyle x} 572:{\displaystyle S} 552:{\displaystyle x} 532:{\displaystyle S} 508:{\displaystyle x} 457:(respectively, a 397:{\displaystyle n} 354:{\displaystyle V} 334:{\displaystyle x} 314:{\displaystyle X} 300:topological space 205:{\displaystyle S} 185:{\displaystyle x} 165:{\displaystyle S} 145:{\displaystyle x} 121:{\displaystyle S} 101:{\displaystyle x} 81:{\displaystyle X} 67:topological space 58:{\displaystyle S} 7026: 7019:General topology 6986: 6985: 6959: 6958: 6949: 6939: 6929: 6928: 6917: 6916: 6711: 6624: 6617: 6610: 6601: 6596: 6578: 6540: 6510: 6459: 6453: 6447: 6446: 6444: 6443: 6428: 6422: 6421: 6414: 6408: 6407: 6400: 6394: 6388: 6382: 6376: 6325: 6316: 6294: 6292: 6291: 6286: 6271: 6269: 6268: 6263: 6251: 6249: 6248: 6243: 6231: 6229: 6228: 6223: 6208: 6206: 6205: 6200: 6170: 6168: 6167: 6162: 6147: 6145: 6144: 6139: 6121: 6119: 6118: 6113: 6101: 6099: 6098: 6093: 6078: 6076: 6075: 6070: 6058: 6056: 6055: 6050: 6038: 6036: 6035: 6030: 6017:trivial topology 6014: 6012: 6011: 6006: 5991: 5989: 5988: 5983: 5968: 5966: 5965: 5960: 5948: 5946: 5945: 5940: 5919: 5917: 5916: 5911: 5893: 5891: 5890: 5885: 5867: 5865: 5864: 5859: 5847: 5845: 5844: 5839: 5820: 5818: 5817: 5812: 5796: 5794: 5793: 5788: 5773: 5771: 5770: 5765: 5750: 5748: 5747: 5742: 5730: 5728: 5727: 5722: 5704: 5702: 5701: 5696: 5669: 5667: 5666: 5661: 5649: 5647: 5646: 5641: 5626: 5624: 5623: 5618: 5606: 5604: 5603: 5598: 5583: 5581: 5580: 5575: 5563: 5561: 5560: 5555: 5540: 5538: 5537: 5532: 5520: 5518: 5517: 5512: 5497: 5495: 5494: 5489: 5477: 5475: 5474: 5469: 5457: 5455: 5454: 5449: 5437: 5435: 5434: 5429: 5414: 5412: 5411: 5406: 5394: 5392: 5391: 5386: 5374: 5372: 5371: 5366: 5354: 5352: 5351: 5346: 5331: 5329: 5328: 5323: 5311: 5309: 5308: 5303: 5288: 5286: 5285: 5280: 5268: 5266: 5265: 5260: 5245: 5243: 5242: 5237: 5225: 5223: 5222: 5217: 5202: 5200: 5199: 5194: 5182: 5180: 5179: 5174: 5159: 5157: 5156: 5151: 5139: 5137: 5136: 5131: 5114: 5112: 5111: 5106: 5092:is contained in 5091: 5089: 5088: 5083: 5062: 5060: 5059: 5054: 5021: 5019: 5018: 5013: 5001: 4999: 4998: 4993: 4971: 4969: 4968: 4963: 4947: 4945: 4944: 4939: 4924: 4922: 4921: 4916: 4904: 4902: 4901: 4896: 4884: 4882: 4881: 4876: 4864: 4862: 4861: 4856: 4844: 4842: 4841: 4836: 4812: 4810: 4809: 4804: 4792: 4790: 4789: 4784: 4769: 4767: 4766: 4761: 4749: 4747: 4746: 4741: 4726: 4724: 4723: 4718: 4706: 4704: 4703: 4698: 4683: 4681: 4680: 4675: 4661: 4659: 4658: 4653: 4629: 4627: 4626: 4621: 4609: 4607: 4606: 4601: 4589: 4587: 4586: 4581: 4570:In other words, 4569: 4567: 4566: 4561: 4546: 4544: 4543: 4538: 4523: 4521: 4520: 4515: 4503: 4501: 4500: 4495: 4480: 4478: 4477: 4472: 4461:we are done. If 4460: 4458: 4457: 4452: 4437: 4435: 4434: 4429: 4417: 4415: 4414: 4409: 4394: 4392: 4391: 4386: 4359: 4357: 4356: 4351: 4327: 4325: 4324: 4319: 4307: 4305: 4304: 4299: 4287: 4285: 4284: 4279: 4267: 4265: 4264: 4259: 4244: 4242: 4241: 4236: 4212: 4210: 4209: 4204: 4177: 4175: 4174: 4169: 4157: 4155: 4154: 4149: 4122: 4120: 4119: 4114: 4102: 4100: 4099: 4094: 4079: 4077: 4076: 4071: 4059: 4057: 4056: 4051: 4039: 4037: 4036: 4031: 4016: 4014: 4013: 4008: 3990: 3988: 3987: 3982: 3951: 3949: 3948: 3943: 3925: 3923: 3922: 3917: 3897: 3895: 3894: 3889: 3850: 3847: 3792: 3790: 3789: 3784: 3763: 3761: 3760: 3755: 3730: 3728: 3727: 3722: 3710: 3708: 3707: 3702: 3658: 3656: 3655: 3650: 3638: 3636: 3635: 3630: 3618: 3616: 3615: 3610: 3598: 3596: 3595: 3590: 3574: 3572: 3571: 3566: 3543: 3541: 3540: 3535: 3523: 3521: 3520: 3515: 3503: 3501: 3500: 3495: 3480: 3478: 3477: 3472: 3467: 3466: 3438: 3436: 3435: 3430: 3428: 3427: 3411: 3409: 3408: 3403: 3391: 3389: 3388: 3383: 3368: 3366: 3365: 3360: 3339: 3337: 3336: 3331: 3326: 3325: 3303: 3301: 3300: 3295: 3279: 3277: 3276: 3271: 3266: 3265: 3243: 3241: 3240: 3235: 3233: 3232: 3210: 3208: 3207: 3202: 3190: 3188: 3187: 3182: 3168: 3167: 3145: 3143: 3142: 3137: 3122: 3120: 3119: 3114: 3109: 3108: 3086: 3084: 3083: 3078: 3066: 3064: 3063: 3058: 3046: 3044: 3043: 3038: 3016: 3014: 3013: 3008: 3006: 3002: 3001: 2987: 2986: 2969: 2968: 2943: 2941: 2940: 2935: 2927: 2919: 2918: 2902: 2900: 2899: 2894: 2882: 2880: 2879: 2874: 2871: 2866: 2855: 2851: 2850: 2833: 2832: 2796: 2794: 2793: 2788: 2769: 2767: 2766: 2761: 2749: 2747: 2746: 2741: 2711: 2709: 2708: 2703: 2701: 2700: 2678: 2676: 2675: 2670: 2659: 2658: 2642: 2640: 2639: 2634: 2622: 2620: 2619: 2614: 2599: 2597: 2596: 2591: 2578: 2577: 2568: 2567: 2561:is said to be a 2560: 2558: 2557: 2552: 2534: 2532: 2531: 2526: 2510: 2508: 2507: 2502: 2478: 2476: 2475: 2470: 2416: 2414: 2413: 2408: 2396: 2394: 2393: 2388: 2377:to mean a point 2365: 2363: 2362: 2357: 2352: 2351: 2335: 2333: 2332: 2327: 2315: 2313: 2312: 2307: 2305: 2304: 2288: 2286: 2285: 2280: 2256: 2254: 2253: 2248: 2236: 2234: 2233: 2228: 2217: 2216: 2200: 2198: 2197: 2192: 2190: 2189: 2167: 2165: 2164: 2159: 2154: 2146: 2145: 2129: 2127: 2126: 2121: 2109: 2107: 2106: 2101: 2089: 2087: 2086: 2081: 2070: 2069: 2053: 2051: 2050: 2045: 2043: 2025: 2023: 2022: 2017: 2002: 2000: 1999: 1994: 1979: 1977: 1976: 1971: 1968: 1963: 1952: 1948: 1947: 1930: 1929: 1913: 1912: 1905: 1904: 1899:is said to be a 1898: 1896: 1895: 1890: 1872: 1870: 1869: 1864: 1830: 1828: 1827: 1822: 1806: 1805: 1799: 1797: 1796: 1791: 1779: 1777: 1776: 1771: 1756: 1754: 1753: 1748: 1726: 1724: 1723: 1718: 1706: 1704: 1703: 1698: 1684: 1682: 1681: 1676: 1655: 1653: 1652: 1647: 1635: 1633: 1632: 1627: 1611:uncountably many 1608: 1606: 1605: 1600: 1586: 1584: 1583: 1578: 1562: 1561: 1555: 1553: 1552: 1547: 1535: 1533: 1532: 1527: 1512: 1510: 1509: 1504: 1485: 1483: 1482: 1477: 1458: 1456: 1455: 1450: 1435: 1433: 1432: 1427: 1408: 1406: 1405: 1400: 1372: 1370: 1369: 1364: 1352: 1350: 1349: 1344: 1314: 1312: 1311: 1306: 1291: 1289: 1288: 1283: 1281: 1280: 1264: 1262: 1261: 1256: 1241: 1239: 1238: 1233: 1221: 1219: 1218: 1213: 1201: 1199: 1198: 1193: 1169: 1167: 1166: 1161: 1159: 1158: 1141: 1139: 1138: 1133: 1114: 1112: 1111: 1106: 1094: 1092: 1091: 1086: 1074: 1072: 1071: 1066: 1050: 1048: 1047: 1042: 1030: 1029: 1015: 1013: 1012: 1007: 995: 993: 992: 987: 975: 973: 972: 967: 949: 947: 946: 941: 922:. Each positive 920:rational numbers 900: 898: 897: 892: 884: 883: 848: 846: 845: 840: 838: 836: 822: 820: 819: 798: 797: 755: 753: 752: 747: 745: 733: 731: 730: 727:{\displaystyle } 725: 701: 699: 698: 693: 677: 675: 674: 669: 667: 655: 653: 652: 647: 629: 627: 626: 621: 598: 596: 595: 590: 578: 576: 575: 570: 558: 556: 555: 550: 538: 536: 535: 530: 514: 512: 511: 506: 475:net converges to 439: 437: 436: 431: 420: 419: 403: 401: 400: 395: 383: 381: 380: 375: 360: 358: 357: 352: 340: 338: 337: 332: 320: 318: 317: 312: 297: 295: 294: 289: 287: 286: 285: 269: 268: 234: 232: 231: 226: 211: 209: 208: 203: 191: 189: 188: 183: 171: 169: 168: 163: 151: 149: 148: 143: 127: 125: 124: 119: 107: 105: 104: 99: 87: 85: 84: 79: 64: 62: 61: 56: 7034: 7033: 7029: 7028: 7027: 7025: 7024: 7023: 6999: 6998: 6997: 6992: 6923: 6905: 6901:Urysohn's lemma 6862: 6826: 6712: 6703: 6675:low-dimensional 6633: 6628: 6581: 6567: 6543: 6529: 6515:Dugundji, James 6513: 6499: 6471: 6468: 6463: 6462: 6454: 6450: 6441: 6439: 6430: 6429: 6425: 6416: 6415: 6411: 6402: 6401: 6397: 6389: 6385: 6377: 6373: 6368: 6323: 6314: 6301: 6296: 6274: 6273: 6254: 6253: 6234: 6233: 6211: 6210: 6179: 6178: 6150: 6149: 6124: 6123: 6104: 6103: 6081: 6080: 6061: 6060: 6041: 6040: 6039:is a subset of 6021: 6020: 5997: 5996: 5993: 5971: 5970: 5951: 5950: 5922: 5921: 5896: 5895: 5870: 5869: 5850: 5849: 5830: 5829: 5803: 5802: 5779: 5778: 5775: 5753: 5752: 5733: 5732: 5707: 5706: 5687: 5686: 5672: 5652: 5651: 5629: 5628: 5609: 5608: 5586: 5585: 5566: 5565: 5543: 5542: 5523: 5522: 5500: 5499: 5480: 5479: 5460: 5459: 5440: 5439: 5438:By assumption, 5417: 5416: 5397: 5396: 5377: 5376: 5357: 5356: 5334: 5333: 5314: 5313: 5291: 5290: 5271: 5270: 5248: 5247: 5228: 5227: 5205: 5204: 5185: 5184: 5162: 5161: 5142: 5141: 5122: 5121: 5094: 5093: 5065: 5064: 5063:if and only if 5024: 5023: 5004: 5003: 4984: 4983: 4954: 4953: 4950: 4927: 4926: 4907: 4906: 4887: 4886: 4867: 4866: 4847: 4846: 4815: 4814: 4795: 4794: 4772: 4771: 4752: 4751: 4729: 4728: 4709: 4708: 4686: 4685: 4666: 4665: 4632: 4631: 4612: 4611: 4592: 4591: 4572: 4571: 4549: 4548: 4526: 4525: 4506: 4505: 4483: 4482: 4463: 4462: 4440: 4439: 4420: 4419: 4397: 4396: 4377: 4376: 4330: 4329: 4310: 4309: 4290: 4289: 4270: 4269: 4247: 4246: 4218: 4217: 4214: 4180: 4179: 4160: 4159: 4158:if and only if 4125: 4124: 4105: 4104: 4082: 4081: 4062: 4061: 4042: 4041: 4019: 4018: 3999: 3998: 3958: 3957: 3928: 3927: 3902: 3901: 3795: 3794: 3766: 3765: 3737: 3736: 3713: 3712: 3681: 3680: 3666: 3641: 3640: 3621: 3620: 3601: 3600: 3581: 3580: 3551: 3550: 3526: 3525: 3506: 3505: 3486: 3485: 3458: 3441: 3440: 3419: 3414: 3413: 3394: 3393: 3371: 3370: 3345: 3344: 3317: 3306: 3305: 3286: 3285: 3257: 3246: 3245: 3224: 3213: 3212: 3193: 3192: 3159: 3148: 3147: 3125: 3124: 3100: 3089: 3088: 3069: 3068: 3049: 3048: 3023: 3022: 2978: 2977: 2973: 2960: 2949: 2948: 2910: 2905: 2904: 2885: 2884: 2842: 2838: 2824: 2819: 2818: 2817:Every sequence 2815: 2776: 2775: 2752: 2751: 2714: 2713: 2692: 2681: 2680: 2650: 2645: 2644: 2625: 2624: 2605: 2604: 2582: 2581: 2575: 2574: 2565: 2564: 2537: 2536: 2517: 2516: 2481: 2480: 2434: 2433: 2399: 2398: 2379: 2378: 2343: 2338: 2337: 2318: 2317: 2316:if and only if 2296: 2291: 2290: 2271: 2270: 2239: 2238: 2208: 2203: 2202: 2181: 2170: 2169: 2137: 2132: 2131: 2112: 2111: 2092: 2091: 2061: 2056: 2055: 2028: 2027: 2005: 2004: 1985: 1984: 1939: 1935: 1921: 1916: 1915: 1910: 1909: 1902: 1901: 1875: 1874: 1852: 1851: 1848: 1836: 1810: 1809: 1803: 1802: 1782: 1781: 1759: 1758: 1733: 1732: 1709: 1708: 1689: 1688: 1664: 1663: 1638: 1637: 1615: 1614: 1591: 1590: 1566: 1565: 1559: 1558: 1538: 1537: 1515: 1514: 1495: 1494: 1491: 1465: 1464: 1441: 1440: 1415: 1414: 1379: 1378: 1355: 1354: 1329: 1328: 1297: 1296: 1272: 1267: 1266: 1244: 1243: 1224: 1223: 1204: 1203: 1178: 1177: 1150: 1145: 1144: 1124: 1123: 1097: 1096: 1095:different from 1077: 1076: 1057: 1056: 1033: 1032: 1027: 1026: 998: 997: 978: 977: 955: 954: 932: 931: 912: 907: 875: 861: 860: 826: 811: 789: 784: 783: 736: 735: 704: 703: 684: 683: 658: 657: 632: 631: 612: 611: 610:. For example, 608:boundary points 581: 580: 561: 560: 541: 540: 521: 520: 497: 496: 486:adherent points 411: 406: 405: 386: 385: 363: 362: 343: 342: 323: 322: 303: 302: 270: 260: 252: 251: 214: 213: 194: 193: 174: 173: 154: 153: 134: 133: 110: 109: 90: 89: 70: 69: 47: 46: 28: 17: 12: 11: 5: 7032: 7030: 7022: 7021: 7016: 7011: 7001: 7000: 6994: 6993: 6991: 6990: 6980: 6979: 6978: 6973: 6968: 6953: 6943: 6933: 6921: 6910: 6907: 6906: 6904: 6903: 6898: 6893: 6888: 6883: 6878: 6872: 6870: 6864: 6863: 6861: 6860: 6855: 6850: 6848:Winding number 6845: 6840: 6834: 6832: 6828: 6827: 6825: 6824: 6819: 6814: 6809: 6804: 6799: 6794: 6789: 6788: 6787: 6782: 6780:homotopy group 6772: 6771: 6770: 6765: 6760: 6755: 6750: 6740: 6735: 6730: 6720: 6718: 6714: 6713: 6706: 6704: 6702: 6701: 6696: 6691: 6690: 6689: 6679: 6678: 6677: 6667: 6662: 6657: 6652: 6647: 6641: 6639: 6635: 6634: 6629: 6627: 6626: 6619: 6612: 6604: 6598: 6597: 6579: 6565: 6541: 6527: 6511: 6497: 6467: 6464: 6461: 6460: 6448: 6423: 6409: 6395: 6383: 6370: 6369: 6367: 6364: 6363: 6362: 6356: 6350: 6344: 6341:Isolated point 6338: 6332: 6326: 6317: 6308: 6305:Adherent point 6300: 6297: 6284: 6281: 6261: 6241: 6221: 6218: 6198: 6195: 6192: 6189: 6186: 6172: 6160: 6157: 6137: 6134: 6131: 6111: 6091: 6088: 6068: 6048: 6028: 6004: 5981: 5978: 5958: 5938: 5935: 5932: 5929: 5909: 5906: 5903: 5883: 5880: 5877: 5857: 5837: 5823: 5810: 5786: 5763: 5760: 5740: 5720: 5717: 5714: 5694: 5680: 5676:isolated point 5659: 5639: 5636: 5616: 5596: 5593: 5573: 5553: 5550: 5530: 5510: 5507: 5487: 5467: 5447: 5427: 5424: 5404: 5384: 5364: 5344: 5341: 5321: 5301: 5298: 5278: 5258: 5255: 5235: 5215: 5212: 5192: 5172: 5169: 5149: 5129: 5104: 5101: 5081: 5078: 5075: 5072: 5052: 5049: 5046: 5043: 5040: 5037: 5034: 5031: 5011: 4991: 4974: 4961: 4937: 4934: 4914: 4894: 4874: 4854: 4834: 4831: 4828: 4825: 4822: 4802: 4782: 4779: 4759: 4739: 4736: 4727:clearly meets 4716: 4696: 4693: 4673: 4651: 4648: 4645: 4642: 4639: 4619: 4599: 4579: 4559: 4556: 4536: 4533: 4513: 4493: 4490: 4470: 4450: 4447: 4427: 4407: 4404: 4384: 4370: 4363: 4349: 4346: 4343: 4340: 4337: 4317: 4297: 4277: 4257: 4254: 4234: 4231: 4228: 4225: 4202: 4199: 4196: 4193: 4190: 4187: 4167: 4147: 4144: 4141: 4138: 4135: 4132: 4112: 4092: 4089: 4069: 4049: 4029: 4026: 4006: 3992: 3980: 3977: 3974: 3971: 3968: 3965: 3941: 3938: 3935: 3915: 3912: 3909: 3887: 3884: 3881: 3878: 3875: 3872: 3869: 3866: 3863: 3860: 3857: 3854: 3844: 3841: 3838: 3835: 3832: 3829: 3826: 3823: 3820: 3817: 3814: 3811: 3808: 3805: 3802: 3782: 3779: 3776: 3773: 3753: 3750: 3747: 3744: 3733:disjoint union 3720: 3700: 3697: 3694: 3691: 3688: 3674:adherent point 3665: 3662: 3661: 3660: 3648: 3628: 3608: 3588: 3578: 3564: 3561: 3558: 3546: 3545: 3533: 3513: 3493: 3470: 3465: 3461: 3457: 3454: 3451: 3448: 3426: 3422: 3401: 3381: 3378: 3358: 3355: 3352: 3341: 3340: 3329: 3324: 3320: 3316: 3313: 3293: 3281: 3280: 3269: 3264: 3260: 3256: 3253: 3231: 3227: 3223: 3220: 3200: 3180: 3177: 3174: 3171: 3166: 3162: 3158: 3155: 3135: 3132: 3112: 3107: 3103: 3099: 3096: 3076: 3056: 3036: 3033: 3030: 3005: 3000: 2996: 2993: 2990: 2985: 2981: 2976: 2972: 2967: 2963: 2959: 2956: 2933: 2930: 2926: 2922: 2917: 2913: 2892: 2870: 2865: 2862: 2859: 2854: 2849: 2845: 2841: 2836: 2831: 2827: 2814: 2811: 2786: 2783: 2759: 2739: 2736: 2733: 2730: 2727: 2724: 2721: 2699: 2695: 2691: 2688: 2679:there is some 2668: 2665: 2662: 2657: 2653: 2632: 2612: 2600:if, for every 2589: 2550: 2547: 2544: 2524: 2500: 2497: 2494: 2491: 2488: 2468: 2465: 2462: 2459: 2456: 2453: 2450: 2447: 2444: 2441: 2420: 2406: 2386: 2355: 2350: 2346: 2325: 2303: 2299: 2278: 2246: 2226: 2223: 2220: 2215: 2211: 2188: 2184: 2180: 2177: 2168:there is some 2157: 2153: 2149: 2144: 2140: 2119: 2099: 2079: 2076: 2073: 2068: 2064: 2042: 2038: 2035: 2015: 2012: 1992: 1980:if, for every 1967: 1962: 1959: 1956: 1951: 1946: 1942: 1938: 1933: 1928: 1924: 1888: 1885: 1882: 1862: 1859: 1835: 1832: 1820: 1817: 1789: 1769: 1766: 1746: 1743: 1740: 1716: 1696: 1674: 1671: 1645: 1625: 1622: 1598: 1576: 1573: 1545: 1525: 1522: 1502: 1490: 1487: 1475: 1472: 1459:is called the 1448: 1425: 1422: 1398: 1395: 1392: 1389: 1386: 1362: 1342: 1339: 1336: 1304: 1279: 1275: 1254: 1251: 1231: 1211: 1191: 1188: 1185: 1157: 1153: 1131: 1104: 1084: 1064: 1040: 1005: 985: 965: 962: 939: 911: 908: 906: 903: 890: 887: 882: 878: 874: 871: 868: 858: 854: 835: 832: 829: 825: 818: 814: 810: 807: 804: 801: 796: 792: 744: 723: 720: 717: 714: 711: 691: 666: 645: 642: 639: 619: 601:isolated point 588: 568: 548: 528: 504: 494: 480: 456: 429: 426: 423: 418: 414: 393: 373: 370: 350: 330: 310: 284: 280: 277: 273: 267: 263: 259: 224: 221: 201: 181: 161: 141: 117: 97: 77: 54: 15: 13: 10: 9: 6: 4: 3: 2: 7031: 7020: 7017: 7015: 7012: 7010: 7007: 7006: 7004: 6989: 6981: 6977: 6974: 6972: 6969: 6967: 6964: 6963: 6962: 6954: 6952: 6948: 6944: 6942: 6938: 6934: 6932: 6927: 6922: 6920: 6912: 6911: 6908: 6902: 6899: 6897: 6894: 6892: 6889: 6887: 6884: 6882: 6879: 6877: 6874: 6873: 6871: 6869: 6865: 6859: 6858:Orientability 6856: 6854: 6851: 6849: 6846: 6844: 6841: 6839: 6836: 6835: 6833: 6829: 6823: 6820: 6818: 6815: 6813: 6810: 6808: 6805: 6803: 6800: 6798: 6795: 6793: 6790: 6786: 6783: 6781: 6778: 6777: 6776: 6773: 6769: 6766: 6764: 6761: 6759: 6756: 6754: 6751: 6749: 6746: 6745: 6744: 6741: 6739: 6736: 6734: 6731: 6729: 6725: 6722: 6721: 6719: 6715: 6710: 6700: 6697: 6695: 6694:Set-theoretic 6692: 6688: 6685: 6684: 6683: 6680: 6676: 6673: 6672: 6671: 6668: 6666: 6663: 6661: 6658: 6656: 6655:Combinatorial 6653: 6651: 6648: 6646: 6643: 6642: 6640: 6636: 6632: 6625: 6620: 6618: 6613: 6611: 6606: 6605: 6602: 6594: 6590: 6589: 6584: 6580: 6576: 6572: 6568: 6562: 6558: 6554: 6550: 6546: 6542: 6538: 6534: 6530: 6524: 6520: 6516: 6512: 6508: 6504: 6500: 6494: 6490: 6486: 6485: 6480: 6479: 6474: 6470: 6469: 6465: 6457: 6452: 6449: 6438:on 2021-04-21 6437: 6433: 6427: 6424: 6420:. 2021-01-13. 6419: 6413: 6410: 6406:. 2021-01-13. 6405: 6399: 6396: 6392: 6391:Bourbaki 1989 6387: 6384: 6380: 6379:Dugundji 1966 6375: 6372: 6365: 6360: 6357: 6354: 6351: 6348: 6345: 6342: 6339: 6336: 6333: 6330: 6327: 6321: 6318: 6312: 6309: 6306: 6303: 6302: 6298: 6295: 6282: 6279: 6259: 6239: 6219: 6216: 6193: 6184: 6171: 6158: 6155: 6135: 6129: 6109: 6089: 6086: 6066: 6046: 6026: 6018: 6002: 5992: 5979: 5976: 5956: 5936: 5933: 5930: 5927: 5904: 5878: 5855: 5835: 5822: 5808: 5800: 5784: 5774: 5761: 5758: 5738: 5715: 5692: 5679: 5677: 5671: 5657: 5637: 5634: 5614: 5594: 5591: 5571: 5551: 5548: 5528: 5508: 5505: 5485: 5465: 5445: 5425: 5422: 5402: 5382: 5362: 5342: 5339: 5319: 5299: 5296: 5276: 5256: 5253: 5233: 5213: 5210: 5190: 5170: 5167: 5147: 5127: 5119: 5115: 5102: 5099: 5076: 5070: 5047: 5041: 5038: 5035: 5032: 5029: 5009: 4989: 4981: 4973: 4959: 4949: 4935: 4932: 4912: 4892: 4872: 4852: 4832: 4826: 4820: 4800: 4780: 4777: 4757: 4737: 4734: 4714: 4694: 4691: 4671: 4662: 4649: 4643: 4637: 4617: 4597: 4577: 4557: 4554: 4534: 4531: 4511: 4491: 4488: 4468: 4448: 4445: 4425: 4405: 4402: 4382: 4369: 4367: 4361: 4347: 4341: 4335: 4315: 4295: 4275: 4255: 4252: 4229: 4223: 4213: 4200: 4194: 4185: 4165: 4145: 4139: 4130: 4110: 4090: 4087: 4067: 4047: 4027: 4024: 4004: 3991: 3978: 3972: 3963: 3955: 3939: 3936: 3933: 3913: 3910: 3907: 3898: 3885: 3879: 3873: 3867: 3864: 3858: 3852: 3839: 3833: 3830: 3824: 3818: 3815: 3809: 3803: 3800: 3777: 3771: 3748: 3742: 3734: 3718: 3695: 3689: 3686: 3677: 3675: 3671: 3663: 3646: 3626: 3606: 3586: 3576: 3562: 3559: 3556: 3548: 3547: 3531: 3511: 3491: 3483: 3482: 3481: 3468: 3463: 3459: 3455: 3452: 3449: 3446: 3424: 3420: 3399: 3379: 3376: 3356: 3353: 3350: 3327: 3322: 3318: 3314: 3311: 3291: 3283: 3282: 3267: 3262: 3258: 3254: 3251: 3229: 3225: 3221: 3218: 3198: 3175: 3169: 3164: 3160: 3156: 3153: 3133: 3130: 3110: 3105: 3101: 3097: 3094: 3074: 3054: 3034: 3031: 3028: 3020: 3019: 3018: 3003: 2994: 2991: 2988: 2983: 2979: 2974: 2970: 2965: 2961: 2957: 2954: 2947: 2931: 2920: 2915: 2911: 2890: 2863: 2860: 2857: 2852: 2847: 2843: 2839: 2834: 2829: 2825: 2812: 2810: 2808: 2804: 2800: 2784: 2781: 2773: 2757: 2737: 2734: 2731: 2725: 2719: 2697: 2693: 2689: 2686: 2666: 2663: 2660: 2655: 2651: 2630: 2610: 2603: 2602:neighbourhood 2587: 2580: 2579: 2570: 2569: 2566:cluster point 2548: 2545: 2542: 2522: 2514: 2495: 2492: 2489: 2466: 2463: 2454: 2451: 2448: 2442: 2439: 2431: 2427: 2422: 2418: 2404: 2384: 2376: 2371: 2369: 2353: 2348: 2344: 2323: 2301: 2297: 2276: 2268: 2264: 2260: 2244: 2224: 2221: 2218: 2213: 2209: 2186: 2182: 2178: 2175: 2155: 2147: 2142: 2138: 2117: 2097: 2077: 2074: 2071: 2066: 2062: 2036: 2033: 2013: 2010: 1990: 1983: 1982:neighbourhood 1960: 1957: 1954: 1949: 1944: 1940: 1936: 1931: 1926: 1922: 1914: 1906: 1903:cluster point 1886: 1883: 1880: 1860: 1857: 1847: 1843: 1838: 1833: 1831: 1818: 1815: 1807: 1787: 1767: 1764: 1744: 1741: 1738: 1730: 1714: 1694: 1685: 1672: 1669: 1661: 1660: 1643: 1623: 1620: 1612: 1596: 1587: 1574: 1571: 1563: 1543: 1523: 1520: 1500: 1488: 1486: 1473: 1470: 1462: 1446: 1437: 1423: 1420: 1412: 1393: 1384: 1377:of points in 1376: 1360: 1340: 1337: 1334: 1326: 1322: 1321:metric spaces 1318: 1302: 1293: 1277: 1273: 1252: 1249: 1229: 1209: 1189: 1186: 1183: 1175: 1171: 1155: 1151: 1129: 1120: 1116: 1102: 1082: 1062: 1054: 1053:neighbourhood 1038: 1031: 1023: 1022:cluster point 1019: 1003: 983: 963: 960: 953: 937: 925: 921: 916: 909: 904: 888: 880: 876: 869: 866: 856: 853: 850: 833: 830: 827: 823: 816: 808: 805: 799: 794: 790: 781: 776: 772: 770: 766: 762: 757: 718: 715: 712: 689: 681: 640: 617: 609: 604: 602: 586: 566: 546: 526: 518: 502: 493: 489: 488:(also called 487: 482: 478: 476: 472: 468: 464: 460: 455: 452: 449: 447: 443: 427: 424: 421: 416: 412: 391: 371: 368: 348: 328: 308: 301: 278: 275: 265: 261: 250: 246: 242: 241:cluster point 238: 222: 219: 199: 179: 159: 139: 131: 130:neighbourhood 115: 95: 75: 68: 52: 45: 41: 40:cluster point 37: 33: 26: 22: 6988:Publications 6853:Chern number 6843:Betti number 6726: / 6717:Key concepts 6665:Differential 6586: 6548: 6518: 6482: 6477: 6456:Munkres 2000 6451: 6440:. Retrieved 6436:the original 6426: 6412: 6398: 6386: 6374: 6252:is empty or 6176: 5994: 5827: 5776: 5684: 5673: 5117: 5116: 4979: 4978: 4951: 4885:(other than 4663: 4374: 4215: 3996: 3899: 3679:The closure 3678: 3667: 3342: 2944:so that its 2816: 2803:limit points 2573: 2563: 2513:directed set 2423: 2372: 2259:metric space 1908: 1900: 1849: 1837: 1801: 1686: 1657: 1588: 1557: 1492: 1438: 1294: 1174:metric space 1121: 1117: 1025: 1021: 1017: 929: 857:limit points 758: 605: 516: 483: 450: 244: 240: 39: 35: 31: 29: 6951:Wikiversity 6868:Key results 6177:As long as 5995:If a space 4080:other than 3793:; that is, 2419:limit point 1729:cardinality 1461:derived set 1327:are), then 1319:(which all 1172:(such as a 1018:limit point 924:real number 682:. However, 321:is a point 172:other than 88:is a point 32:limit point 7009:Limit sets 7003:Categories 6797:CW complex 6738:Continuity 6728:Closed set 6687:cohomology 6466:References 6442:2021-01-14 5203:is not in 4481:is not in 4362:definition 4216:If we use 3664:Properties 2799:Clustering 2712:such that 2643:and every 2201:such that 2130:and every 2054:such that 1840:See also: 1613:points of 905:Definition 765:closed set 490:points of 404:such that 6976:geometric 6971:algebraic 6822:Cobordism 6758:Hausdorff 6753:connected 6670:Geometric 6660:Continuum 6650:Algebraic 6593:EMS Press 6537:395340485 6475:(1989) . 6366:Citations 6188:∖ 6133:∖ 5931:≠ 5670:is open. 5039:∪ 4189:∖ 4134:∖ 3967:∖ 3937:⊆ 3911:∈ 3883:∅ 3865:∩ 3831:∪ 3804:⁡ 3711:of a set 3690:⁡ 3587:ω 3560:∈ 3492:ω 3464:∙ 3456:⁡ 3425:∙ 3354:⊆ 3323:∙ 3315:⁡ 3292:ω 3263:∙ 3255:⁡ 3230:∙ 3222:⁡ 3165:∙ 3157:⁡ 3106:∙ 3098:⁡ 3032:∈ 2995:∈ 2966:∙ 2958:⁡ 2929:→ 2916:∙ 2869:∞ 2830:∙ 2732:∈ 2690:≥ 2661:∈ 2546:∈ 2496:≤ 2461:→ 2455:≤ 2368:limit set 2349:∙ 2302:∙ 2219:∈ 2179:≥ 2148:∈ 2072:∈ 2037:∈ 1966:∞ 1927:∙ 1884:∈ 1742:∩ 1609:contains 1388:∖ 1338:∈ 1265:In fact, 1187:∈ 1115:itself. 1051:if every 806:− 519:point of 515:contains 422:∈ 279:∈ 237:sequences 7014:Topology 6941:Wikibook 6919:Category 6807:Manifold 6775:Homotopy 6733:Interior 6724:Open set 6682:Homology 6631:Topology 6575:42683260 6549:Topology 6547:(2000). 6519:Topology 6517:(1966). 6507:18588129 6299:See also 6015:has the 5799:discrete 5777:A space 3900:A point 3575:that is 3549:A point 3146:we have 2430:sequence 2269:), then 1873:a point 1375:sequence 1176:), then 1119:point. 976:A point 249:sequence 6966:general 6768:uniform 6748:compact 6699:Digital 6595:, 2001 6487:]. 5949:and so 5521:and so 5120:2: Let 4366:closure 3954:closure 2807:filters 849:has no 492:closure 446:filters 6961:Topics 6763:metric 6638:Fields 6573:  6563:  6535:  6525:  6505:  6495:  5269:Since 4905:), so 4813:is in 4684:is in 4630:is in 4438:is in 3668:Every 2772:subnet 2770:has a 2479:where 1844:, and 1409:whose 473:, the 6743:Space 6481:[ 6174:Proof 5825:Proof 5682:Proof 5118:Proof 4980:Proof 4976:Proof 4372:Proof 3994:Proof 3731:is a 3670:limit 2946:image 2511:is a 2261:or a 2257:is a 1780:then 1636:then 1536:then 1411:limit 1315:is a 1170:space 1142:is a 1016:is a 852:limit 761:limit 678:with 298:in a 247:of a 65:in a 42:of a 38:, or 6571:OCLC 6561:ISBN 6533:OCLC 6523:ISBN 6503:OCLC 6493:ISBN 6019:and 4610:and 4328:and 3484:Any 3191:and 2801:and 2515:and 1323:and 930:Let 767:and 517:some 461:, a 444:and 442:nets 239:. A 23:and 6102:If 5828:If 5797:is 5685:If 5674:No 5478:of 5183:If 4982:1: 4793:If 4750:so 4418:If 4364:of 3956:of 3848:and 3579:an 3577:not 3369:in 2883:in 2623:of 2571:or 2426:net 2370:. 2237:If 2110:of 2003:of 1907:or 1808:of 1731:of 1707:of 1662:of 1564:of 1463:of 1413:is 1295:If 1122:If 1055:of 1024:or 1020:or 996:in 734:in 690:0.5 656:in 559:of 479:not 448:. 361:of 243:or 132:of 44:set 7005:: 6591:, 6585:, 6569:. 6559:. 6555:: 6531:. 6501:. 4368:. 3801:cl 3687:cl 3676:. 3453:Im 3312:Im 3252:Im 3219:Im 3154:Im 3095:Im 2971::= 2955:Im 2809:. 603:. 34:, 6623:e 6616:t 6609:v 6577:. 6539:. 6509:. 6445:. 6283:. 6280:S 6260:x 6240:S 6220:. 6217:X 6197:} 6194:x 6191:{ 6185:S 6159:. 6156:S 6136:S 6130:X 6110:S 6090:. 6087:S 6067:X 6047:X 6027:S 6003:X 5980:. 5977:X 5957:x 5937:, 5934:x 5928:y 5908:} 5905:x 5902:{ 5882:} 5879:x 5876:{ 5856:X 5836:X 5809:X 5785:X 5762:. 5759:x 5739:x 5719:} 5716:x 5713:{ 5693:x 5658:S 5638:. 5635:S 5615:S 5595:, 5592:S 5572:x 5552:. 5549:S 5529:U 5509:, 5506:S 5486:x 5466:U 5446:x 5426:. 5423:S 5403:x 5383:S 5363:S 5343:. 5340:S 5320:x 5300:, 5297:S 5277:x 5257:. 5254:x 5234:S 5214:, 5211:S 5191:x 5171:. 5168:S 5148:x 5128:S 5103:. 5100:S 5080:) 5077:S 5074:( 5071:L 5051:) 5048:S 5045:( 5042:L 5036:S 5033:= 5030:S 5010:S 4990:S 4960:S 4936:. 4933:S 4913:x 4893:x 4873:S 4853:x 4833:, 4830:) 4827:S 4824:( 4821:L 4801:x 4781:. 4778:S 4758:x 4738:, 4735:S 4715:x 4695:, 4692:S 4672:x 4650:. 4647:) 4644:S 4641:( 4638:L 4618:x 4598:S 4578:x 4558:. 4555:x 4535:, 4532:S 4512:x 4492:, 4489:S 4469:x 4449:, 4446:S 4426:x 4406:. 4403:S 4383:x 4348:. 4345:) 4342:S 4339:( 4336:L 4316:S 4296:S 4276:S 4256:, 4253:S 4233:) 4230:S 4227:( 4224:L 4201:. 4198:} 4195:x 4192:{ 4186:S 4166:x 4146:, 4143:} 4140:x 4137:{ 4131:S 4111:x 4091:, 4088:x 4068:S 4048:x 4028:, 4025:S 4005:x 3979:. 3976:} 3973:x 3970:{ 3964:S 3940:X 3934:S 3914:X 3908:x 3886:. 3880:= 3877:) 3874:S 3871:( 3868:I 3862:) 3859:S 3856:( 3853:L 3843:) 3840:S 3837:( 3834:I 3828:) 3825:S 3822:( 3819:L 3816:= 3813:) 3810:S 3807:( 3781:) 3778:S 3775:( 3772:I 3752:) 3749:S 3746:( 3743:L 3719:S 3699:) 3696:S 3693:( 3647:A 3627:x 3607:A 3563:X 3557:x 3532:A 3512:A 3469:. 3460:x 3450:= 3447:A 3421:x 3400:A 3380:, 3377:X 3357:X 3351:A 3328:. 3319:x 3268:. 3259:x 3226:x 3199:x 3179:} 3176:x 3173:{ 3170:= 3161:x 3134:, 3131:x 3111:. 3102:x 3075:x 3055:x 3035:X 3029:x 3004:} 2999:N 2992:n 2989:: 2984:n 2980:x 2975:{ 2962:x 2932:X 2925:N 2921:: 2912:x 2891:X 2864:1 2861:= 2858:n 2853:) 2848:n 2844:x 2840:( 2835:= 2826:x 2785:. 2782:x 2758:f 2738:, 2735:V 2729:) 2726:p 2723:( 2720:f 2698:0 2694:p 2687:p 2667:, 2664:P 2656:0 2652:p 2631:x 2611:V 2588:f 2549:X 2543:x 2523:X 2499:) 2493:, 2490:P 2487:( 2467:, 2464:X 2458:) 2452:, 2449:P 2446:( 2443:: 2440:f 2405:x 2385:x 2354:. 2345:x 2324:x 2298:x 2277:x 2245:X 2225:. 2222:V 2214:n 2210:x 2187:0 2183:n 2176:n 2156:, 2152:N 2143:0 2139:n 2118:x 2098:V 2078:. 2075:V 2067:n 2063:x 2041:N 2034:n 2014:, 2011:x 1991:V 1961:1 1958:= 1955:n 1950:) 1945:n 1941:x 1937:( 1932:= 1923:x 1887:X 1881:x 1861:, 1858:X 1819:. 1816:S 1788:x 1768:, 1765:S 1745:S 1739:U 1715:x 1695:U 1673:. 1670:S 1644:x 1624:, 1621:S 1597:x 1575:. 1572:S 1544:x 1524:, 1521:S 1501:x 1474:. 1471:S 1447:S 1424:. 1421:x 1397:} 1394:x 1391:{ 1385:S 1361:S 1341:X 1335:x 1303:X 1278:1 1274:T 1253:. 1250:S 1230:x 1210:S 1190:X 1184:x 1156:1 1152:T 1130:X 1103:x 1083:S 1063:x 1039:S 1004:X 984:x 964:. 961:X 938:S 889:. 886:} 881:n 877:x 873:{ 870:= 867:S 834:1 831:+ 828:n 824:n 817:n 813:) 809:1 803:( 800:= 795:n 791:x 743:R 722:] 719:1 716:, 713:0 710:[ 665:R 644:} 641:0 638:{ 618:0 587:x 567:S 547:x 527:S 503:x 428:. 425:V 417:n 413:x 392:n 372:, 369:x 349:V 329:x 309:X 283:N 276:n 272:) 266:n 262:x 258:( 223:. 220:S 200:S 180:x 160:S 140:x 116:S 96:x 76:X 53:S 27:.

Index

Limit (mathematics)
Limit (disambiguation) § Mathematics
set
topological space
neighbourhood
sequences
sequence
topological space
nets
filters
limit point of a sequence
limit point of a filter
limit point of a net
sequence converges to
filter converges to
net converges to
adherent points
closure
isolated point
boundary points
standard topology
limit
closed set
topological closure

Euclidean topology
limit

rational numbers
real number

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

↑