Knowledge (XXG)

Friedman number

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4633: 2541:
numbering systems) but with the numbers of symbols it has. For example, it is much tougher to figure out whether 147 (CXLVII) is a Friedman number in Roman numerals than it is to make the same determination for 1001 (MI). With Roman numerals, one can at least derive quite a few Friedman expressions
260:
127, 343, 736, 1285, 2187, 2502, 2592, 2737, 3125, 3685, 3864, 3972, 4096, 6455, 11264, 11664, 12850, 13825, 14641, 15552, 15585, 15612, 15613, 15617, 15618, 15621, 15622, 15623, 15624, 15626, 15632, 15633, 15642, 15645, 15655, 15656, 15662, 15667, 15688, 16377, 16384, 16447, 16875, 17536, 18432,
94:
127, 347, 2503, 12101, 12107, 12109, 15629, 15641, 15661, 15667, 15679, 16381, 16447, 16759, 16879, 19739, 21943, 27653, 28547, 28559, 29527, 29531, 32771, 32783, 35933, 36457, 39313, 39343, 43691, 45361, 46619, 46633, 46643, 46649, 46663, 46691, 48751, 48757, 49277, 58921, 59051, 59053, 59263,
287:
127, 15667, 16447, 19739, 28559, 32771, 39343, 46633, 46663, 117619, 117643, 117763, 125003, 131071, 137791, 147419, 156253, 156257, 156259, 229373, 248839, 262139, 262147, 279967, 294829, 295247, 326617, 466553, 466561, 466567, 585643, 592763, 649529, 728993, 759359, 786433, 937577 (sequence
2533:
Some research into Roman numeral Friedman numbers for which the expression uses some of the other operators has been done. The first such nice Roman numeral Friedman number discovered was 8, since VIII = (V - I) × II. Other such nontrivial examples have been found.
56:
25, 121, 125, 126, 127, 128, 153, 216, 289, 343, 347, 625, 688, 736, 1022, 1024, 1206, 1255, 1260, 1285, 1296, 1395, 1435, 1503, 1530, 1792, 1827, 2048, 2187, 2349, 2500, 2501, 2502, 2503, 2504, 2505, 2506, 2507, 2508, 2509, 2592, 2737, 2916, ... (sequence
310:
tends to infinity. This result extends to Friedman numbers under any base of representation. He also proved that the same is true also for binary, ternary and quaternary nice Friedman numbers. The case of base-10 nice Friedman numbers is still open.
2373: 48:. Here, non-trivial means that at least one operation besides concatenation is used. Leading zeros cannot be used, since that would also result in trivial Friedman numbers, such as 024 = 20 + 4. For example, 347 is a Friedman number in the 255:
Friedman number is a Friedman number where the digits in the expression can be arranged to be in the same order as in the number itself. For example, we can arrange 127 = 2 − 1 as 127 = −1 + 2. The first nice Friedman numbers are:
2226: 2117: 2008: 1899: 1753: 1389: 1644: 1156: 1474: 1553: 2529:
with more than one symbol are Friedman numbers. The expression is created by simply inserting + signs into the numeral, and occasionally the − sign with slight rearrangement of the order of the symbols.
782: 937: 1039: 2542:
from any new expression one discovers. Since 8 is a nice nontrivial nice Roman numeral Friedman number, it follows that any number ending in VIII is also such a Friedman number.
2735: 2263: 302:
Michael Brand proved that the density of Friedman numbers among the naturals is 1, which is to say that the probability of a number chosen randomly and uniformly between 1 and
1789: 1297: 2514: 325:
There usually are fewer 2-digit Friedman numbers than 3-digit and more in any given base, but the 2-digit ones are easier to find. If we represent a 2-digit number as
2256: 846: 659: 2425: 2511: 1225: 986: 2642: 2485: 2465: 2445: 2396: 1179: 960: 805: 448:
The first few known Friedman numbers in other small bases are shown below, written in their respective bases. Numbers shown in bold are nice Friedman numbers.
317:
are a subset of Friedman numbers where the only operation is a multiplication of two numbers with the same number of digits, for example 1260 = 21 × 60.
4662: 4657: 295: 268: 102: 64: 2124: 2015: 1906: 1797: 1651: 2728: 1305: 1560: 1047: 1396: 3535: 2721: 2537:
The difficulty of finding nontrivial Friedman numbers in Roman numerals increases not with the size of the number (as is the case with
3530: 3545: 3525: 1481: 4238: 3818: 3540: 4324: 667: 3640: 3990: 3309: 3102: 1231:, 250068 = 500 + 68, from which we can easily deduce the range of consecutive Friedman numbers from 250000 to 250099 in 4025: 3995: 3670: 3660: 854: 4166: 3580: 3314: 3294: 3856: 4020: 4115: 3738: 3495: 3304: 3286: 3180: 3170: 3160: 4000: 4243: 3788: 3409: 3195: 3190: 3185: 3175: 3152: 3228: 2638: 3485: 4354: 4319: 4105: 4015: 3889: 3864: 3773: 3763: 3375: 3357: 3277: 994: 4614: 3884: 3758: 3389: 3165: 2945: 2872: 2368:{\displaystyle n\times 10^{50}+{\text{15AA51}}=n\times 10^{50}+(10+{\text{A}}/{\text{A}})^{5}+0+0+\ldots } 49: 3869: 3723: 3650: 2805: 1201:
0's, we can find sequences of consecutive Friedman numbers which are arbitrarily long. For example, for
4578: 4218: 2663: 4511: 4405: 4369: 4110: 3833: 3813: 3630: 3299: 3087: 3059: 1762: 4233: 4097: 4092: 4060: 3823: 3798: 3793: 3768: 3698: 3694: 3625: 3515: 3347: 3143: 3112: 2538: 1270: 4632: 4636: 4390: 4385: 4299: 4273: 4171: 4150: 3922: 3803: 3753: 3675: 3645: 3585: 3352: 3332: 3263: 2976: 76: 3520: 4530: 4475: 4329: 4304: 4278: 4055: 3733: 3728: 3655: 3635: 3620: 3342: 3324: 3243: 3233: 3218: 2996: 2981: 2235: 4566: 4359: 3945: 3917: 3907: 3899: 3783: 3748: 3743: 3710: 3404: 3367: 3258: 3253: 3248: 3238: 3210: 3097: 3049: 3044: 3001: 2940: 2675: 2590: 825: 629: 37: 72: 4542: 4364: 4290: 4213: 4187: 4005: 3718: 3575: 3510: 3480: 3470: 3465: 3131: 3039: 2986: 2830: 2770: 2401: 33: 2490: 1204: 965: 4547: 4415: 4400: 4264: 4228: 4203: 4079: 4050: 4035: 3912: 3808: 3778: 3505: 3460: 3337: 2935: 2930: 2925: 2897: 2882: 2795: 2780: 2758: 2745: 2613: 2470: 2450: 2430: 2381: 1164: 945: 790: 314: 41: 29: 1267:
There are an infinite number of prime Friedman numbers in all bases, because for base
4651: 4470: 4454: 4395: 4349: 4045: 4030: 3940: 3665: 3223: 3092: 3054: 3011: 2892: 2877: 2867: 2825: 2815: 2790: 2526: 442: 45: 4506: 4495: 4410: 4248: 4223: 4140: 4040: 4010: 3985: 3969: 3874: 3841: 3590: 3564: 3475: 3414: 2991: 2887: 2820: 2800: 2775: 87: 2650: 4465: 4340: 4145: 3609: 3500: 3455: 3450: 3200: 3107: 3006: 2835: 2810: 2785: 2221:{\displaystyle n\times 10^{60}+161051=n\times 10^{60}+(10+1-0)^{5}+0+0+\ldots } 2112:{\displaystyle n\times 10^{60}+162151=n\times 10^{60}+(10+2-1)^{5}+0+0+\ldots } 2003:{\displaystyle n\times 10^{60}+163251=n\times 10^{60}+(10+3-2)^{5}+0+0+\ldots } 1894:{\displaystyle n\times 10^{60}+164351=n\times 10^{60}+(10+4-3)^{5}+0+0+\ldots } 1748:{\displaystyle n\times 10^{13}+25352411=n\times 10^{2\times 5-1}+(5+2)^{(3+4)}} 4602: 4583: 3879: 3490: 2680: 2713: 36:
in combination with any of the four basic arithmetic operators (+, −, ×, Ă·),
4208: 4135: 4127: 3932: 3846: 2964: 1384:{\displaystyle n\times 10^{1111}+11111111=n\times 10^{1111}+10^{1000}-1+0+0} 437:
Friedman numbers also exist for bases other than base 10. For example, 11001
4309: 1639:{\displaystyle n\times 10^{13}+2443111=n\times 10^{4+4}+(2\times 3)^{11}} 1260: 1238: 1151:{\displaystyle 2b+k=2\left({\frac {k(k-1)}{2}}\right)+k=k^{2}-k+k=k^{2}} 4314: 3973: 1253: 1232: 1228: 283:
Friedman number that's also prime. The first nice Friedman primes are:
21: 1256:
that is thought to be a Friedman number is 99999999 = (9 + 9/9) − 9/9.
1469:{\displaystyle n\times 10^{102}+1101221=n\times 10^{102}+2^{101}+0+0} 1246: 2697: 2576: 2688: 2630: 25: 4600: 4564: 4528: 4492: 4452: 4077: 3966: 3692: 3607: 3562: 3439: 3129: 3076: 3028: 2962: 2914: 2852: 2756: 2717: 1548:{\displaystyle n\times 10^{20}+310233=n\times 10^{20}+33^{3}+0} 381:
to see which ones are true. We need not concern ourselves with
32:, is the result of a non-trivial expression using all its own 2575:
Michael Brand, "On the Density of Nice Friedmans", Oct 2013,
2691: 2633: 290: 263: 97: 59: 2692:
sequence A119710 (Radical narcissistic numbers)
95:
59273, 64513, 74353, 74897, 78163, 83357, ... (sequence
114:
The expressions of the first few Friedman numbers are:
52:, since 347 = 7 + 4. The decimal Friedman numbers are: 2517:, the sequence contains an infinite number of primes. 2398:. The numbers of this form are an arithmetic sequence 1189:). From the observation that all numbers of the form 2 2698:"Pretty wild narcissistic numbers - numbers that pwn" 2493: 2473: 2453: 2433: 2404: 2384: 2266: 2238: 2127: 2018: 1909: 1800: 1765: 1654: 1563: 1484: 1399: 1308: 1273: 1207: 1167: 1050: 997: 968: 948: 857: 828: 793: 670: 632: 777:{\displaystyle b^{2}+mb+k=(mk-m+m)b+k=mbk+k=k(mb+1)} 349:−1, we need only check each possible combination of 4424: 4378: 4338: 4289: 4263: 4196: 4180: 4159: 4126: 4091: 3931: 3898: 3855: 3832: 3709: 3397: 3388: 3366: 3323: 3285: 3276: 3209: 3151: 3142: 2558:Michael Brand, "Friedman numbers have density 1", 2505: 2479: 2459: 2439: 2419: 2390: 2367: 2250: 2220: 2111: 2002: 1893: 1783: 1747: 1638: 1547: 1468: 1383: 1291: 1263:with at least 22 digits are nice Friedman numbers. 1219: 1173: 1150: 1033: 980: 954: 931: 840: 799: 776: 653: 932:{\displaystyle {(b^{n}+1)}^{2}=b^{2n}+2{b^{n}}+1} 2513:are always relatively prime, and therefore, by 2515:Dirichlet's theorem on arithmetic progressions 2729: 2643:The On-Line Encyclopedia of Integer Sequences 8: 2634:sequence A036057 (Friedman number) 2467:are relatively prime regardless of base as 4597: 4561: 4525: 4489: 4449: 4123: 4088: 4074: 3963: 3706: 3689: 3604: 3559: 3436: 3394: 3282: 3148: 3139: 3126: 3073: 3030:Possessing a specific set of other numbers 3025: 2959: 2911: 2849: 2753: 2736: 2722: 2714: 397:, since these will always be smaller than 2679: 2492: 2472: 2452: 2432: 2403: 2383: 2341: 2332: 2327: 2322: 2304: 2286: 2277: 2265: 2237: 2194: 2163: 2138: 2126: 2085: 2054: 2029: 2017: 1976: 1945: 1920: 1908: 1867: 1836: 1811: 1799: 1764: 1727: 1690: 1665: 1653: 1630: 1599: 1574: 1562: 1533: 1520: 1495: 1483: 1448: 1435: 1410: 1398: 1357: 1344: 1319: 1307: 1272: 1206: 1166: 1142: 1117: 1073: 1049: 1004: 996: 967: 947: 916: 911: 896: 883: 867: 859: 856: 827: 792: 675: 669: 631: 79:and recreational mathematics enthusiast. 75:, a now-retired mathematics professor at 450: 116: 2608: 2606: 2604: 2602: 2600: 2551: 1161:is a Friedman number (written in base 962:as 100...00200...001 = 100..001, with 942:is a Friedman number (written in base 787:is a Friedman number (written in base 306:to be a Friedman number tends to 1 as 1034:{\displaystyle b={\frac {k(k-1)}{2}}} 988:zeroes between each nonzero number). 7: 1249:that is a Friedman number is 33 = 3. 90:. The decimal Friedman primes are: 2566:(16–17), Nov. 2013, pp. 2389-2395. 86:is a Friedman number that is also 14: 2664:"Friedman numbers have density 1" 2657:. Problem of the Month. Aug 2000. 2591:"Friedman numbers in other bases" 441:= 25 is a Friedman number in the 71:Friedman numbers are named after 4663:Eponymous numbers in mathematics 4658:Base-dependent integer sequences 4631: 4239:Perfect digit-to-digit invariant 481:121, 221, 1022, 1122, 1211, ... 321:Finding 2-digit Friedman numbers 2577:https://arxiv.org/abs/1310.2390 579:121, 237, 24A, 1245, 1246, ... 563:121, 2A9, 603, 1163, 1533, ... 2702:Theoretical Research Institute 2338: 2313: 2191: 2172: 2082: 2063: 1973: 1954: 1864: 1845: 1784:{\displaystyle 7\leq b\leq 10} 1740: 1728: 1724: 1711: 1627: 1614: 1091: 1079: 1022: 1010: 879: 860: 771: 756: 720: 699: 261:19453, 19683, 19739 (sequence 1: 3078:Expressible via specific sums 2706:Extension to Friedman numbers 2378:are Friedman numbers for all 1292:{\displaystyle 2\leq b\leq 6} 615:121, 129, 145, 183, 27D, ... 571:121, 127, 135, 144, 163, ... 413:. The same clearly holds for 2668:Discrete Applied Mathematics 2560:Discrete Applied Mathematics 4167:Multiplicative digital root 2662:Brand, Michael (Nov 2013). 4679: 543:, 121, 125, 143, 251, ... 4627: 4610: 4596: 4574: 4560: 4538: 4524: 4502: 4488: 4461: 4448: 4244:Perfect digital invariant 4087: 4073: 3981: 3962: 3819:Superior highly composite 3705: 3688: 3616: 3603: 3571: 3558: 3446: 3435: 3138: 3125: 3083: 3072: 3035: 3024: 2972: 2958: 2921: 2910: 2863: 2848: 2766: 2752: 2681:10.1016/j.dam.2013.05.027 1252:The smallest repdigit in 1245:The smallest repdigit in 520:, 52, 121, 124, 133, ... 3857:Euler's totient function 3641:Euler–Jacobi pseudoprime 2916:Other polynomial numbers 2525:In a trivial sense, all 1259:It has been proven that 493:, 1203, 1230, 1321, ... 473:, 1001111, 1010001, ... 3671:Somer–Lucas pseudoprime 3661:Lucas–Carmichael number 3496:Lazy caterer's sequence 2251:{\displaystyle b>10} 357:against the equalities 345:are integers from 0 to 3546:Wedderburn–Etherington 2946:Lucky numbers of Euler 2639:Other Friedman numbers 2507: 2481: 2461: 2441: 2421: 2392: 2369: 2252: 2222: 2113: 2004: 1895: 1785: 1749: 1640: 1549: 1470: 1385: 1293: 1221: 1193:× b can be written as 1175: 1152: 1035: 982: 956: 933: 842: 841:{\displaystyle b>2} 801: 778: 655: 654:{\displaystyle b=mk-m} 50:decimal numeral system 3834:Prime omega functions 3651:Frobenius pseudoprime 3441:Combinatorial numbers 3310:Centered dodecahedral 3103:Primary pseudoperfect 2508: 2482: 2462: 2442: 2422: 2393: 2370: 2253: 2223: 2114: 2005: 1896: 1786: 1750: 1641: 1550: 1471: 1386: 1294: 1222: 1176: 1153: 1036: 983: 957: 934: 843: 802: 779: 656: 445:, since 11001 = 101. 443:binary numeral system 4293:-composition related 4093:Arithmetic functions 3695:Arithmetic functions 3631:Elliptic pseudoprime 3315:Centered icosahedral 3295:Centered tetrahedral 2674:(16–17): 2389–2395. 2521:Using Roman numerals 2491: 2471: 2451: 2431: 2420:{\displaystyle pn+q} 2402: 2382: 2264: 2236: 2125: 2016: 1907: 1798: 1763: 1652: 1561: 1482: 1397: 1306: 1271: 1205: 1165: 1048: 995: 966: 946: 855: 826: 791: 668: 630: 279:Friedman prime is a 4219:Kaprekar's constant 3739:Colossally abundant 3626:Catalan pseudoprime 3526:Schröder–Hipparchus 3305:Centered octahedral 3181:Centered heptagonal 3171:Centered pentagonal 3161:Centered triangular 2761:and related numbers 2539:positional notation 2506:{\displaystyle b+1} 1220:{\displaystyle k=5} 981:{\displaystyle n-1} 603:26, 121, 136, 154, 4637:Mathematics portal 4579:Aronson's sequence 4325:Smarandache–Wellin 4082:-dependent numbers 3789:Primitive abundant 3676:Strong pseudoprime 3666:Perrin pseudoprime 3646:Fermat pseudoprime 3586:Wolstenholme prime 3410:Squared triangular 3196:Centered decagonal 3191:Centered nonagonal 3186:Centered octagonal 3176:Centered hexagonal 2651:"Friedman numbers" 2503: 2477: 2457: 2437: 2417: 2388: 2365: 2248: 2218: 2109: 2000: 1891: 1781: 1745: 1636: 1545: 1466: 1381: 1289: 1241:Friedman numbers: 1217: 1171: 1148: 1031: 978: 952: 929: 838: 797: 774: 651: 110:Results in base 10 77:Stetson University 4645: 4644: 4623: 4622: 4592: 4591: 4556: 4555: 4520: 4519: 4484: 4483: 4444: 4443: 4440: 4439: 4259: 4258: 4069: 4068: 3958: 3957: 3954: 3953: 3900:Aliquot sequences 3711:Divisor functions 3684: 3683: 3656:Lucas pseudoprime 3636:Euler pseudoprime 3621:Carmichael number 3599: 3598: 3554: 3553: 3431: 3430: 3427: 3426: 3423: 3422: 3384: 3383: 3272: 3271: 3229:Square triangular 3121: 3120: 3068: 3067: 3020: 3019: 2954: 2953: 2906: 2905: 2844: 2843: 2589:Friedman, Erich. 2480:{\displaystyle b} 2460:{\displaystyle q} 2440:{\displaystyle p} 2391:{\displaystyle n} 2335: 2325: 2289: 1174:{\displaystyle b} 1098: 1029: 955:{\displaystyle b} 800:{\displaystyle b} 619: 618: 555:, 628, 1304, ... 457:Friedman numbers 249: 248: 38:additive inverses 4670: 4635: 4598: 4567:Natural language 4562: 4526: 4494:Generated via a 4490: 4450: 4355:Digit-reassembly 4320:Self-descriptive 4124: 4089: 4075: 4026:Lucas–Carmichael 4016:Harmonic divisor 3964: 3890:Sparsely totient 3865:Highly cototient 3774:Multiply perfect 3764:Highly composite 3707: 3690: 3605: 3560: 3541:Telephone number 3437: 3395: 3376:Square pyramidal 3358:Stella octangula 3283: 3149: 3140: 3132:Figurate numbers 3127: 3074: 3026: 2960: 2912: 2850: 2754: 2738: 2731: 2724: 2715: 2708: 2690: 2685: 2683: 2658: 2632: 2618: 2617: 2610: 2595: 2594: 2586: 2580: 2573: 2567: 2556: 2512: 2510: 2509: 2504: 2486: 2484: 2483: 2478: 2466: 2464: 2463: 2458: 2446: 2444: 2443: 2438: 2426: 2424: 2423: 2418: 2397: 2395: 2394: 2389: 2374: 2372: 2371: 2366: 2346: 2345: 2336: 2333: 2331: 2326: 2323: 2309: 2308: 2290: 2287: 2282: 2281: 2257: 2255: 2254: 2249: 2227: 2225: 2224: 2219: 2199: 2198: 2168: 2167: 2143: 2142: 2118: 2116: 2115: 2110: 2090: 2089: 2059: 2058: 2034: 2033: 2009: 2007: 2006: 2001: 1981: 1980: 1950: 1949: 1925: 1924: 1900: 1898: 1897: 1892: 1872: 1871: 1841: 1840: 1816: 1815: 1790: 1788: 1787: 1782: 1754: 1752: 1751: 1746: 1744: 1743: 1707: 1706: 1670: 1669: 1645: 1643: 1642: 1637: 1635: 1634: 1610: 1609: 1579: 1578: 1554: 1552: 1551: 1546: 1538: 1537: 1525: 1524: 1500: 1499: 1475: 1473: 1472: 1467: 1453: 1452: 1440: 1439: 1415: 1414: 1390: 1388: 1387: 1382: 1362: 1361: 1349: 1348: 1324: 1323: 1298: 1296: 1295: 1290: 1226: 1224: 1223: 1218: 1180: 1178: 1177: 1172: 1157: 1155: 1154: 1149: 1147: 1146: 1122: 1121: 1103: 1099: 1094: 1074: 1040: 1038: 1037: 1032: 1030: 1025: 1005: 987: 985: 984: 979: 961: 959: 958: 953: 938: 936: 935: 930: 922: 921: 920: 904: 903: 888: 887: 882: 872: 871: 847: 845: 844: 839: 806: 804: 803: 798: 783: 781: 780: 775: 680: 679: 660: 658: 657: 652: 532:, 264, 514, ... 451: 337:is the base and 293: 266: 117: 100: 62: 4678: 4677: 4673: 4672: 4671: 4669: 4668: 4667: 4648: 4647: 4646: 4641: 4619: 4615:Strobogrammatic 4606: 4588: 4570: 4552: 4534: 4516: 4498: 4480: 4457: 4436: 4420: 4379:Divisor-related 4374: 4334: 4285: 4255: 4192: 4176: 4155: 4122: 4095: 4083: 4065: 3977: 3976:related numbers 3950: 3927: 3894: 3885:Perfect totient 3851: 3828: 3759:Highly abundant 3701: 3680: 3612: 3595: 3567: 3550: 3536:Stirling second 3442: 3419: 3380: 3362: 3319: 3268: 3205: 3166:Centered square 3134: 3117: 3079: 3064: 3031: 3016: 2968: 2967:defined numbers 2950: 2917: 2902: 2873:Double Mersenne 2859: 2840: 2762: 2748: 2746:natural numbers 2742: 2696: 2661: 2649: 2627: 2622: 2621: 2612: 2611: 2598: 2588: 2587: 2583: 2574: 2570: 2557: 2553: 2548: 2523: 2489: 2488: 2469: 2468: 2449: 2448: 2429: 2428: 2400: 2399: 2380: 2379: 2337: 2300: 2273: 2262: 2261: 2234: 2233: 2190: 2159: 2134: 2123: 2122: 2081: 2050: 2025: 2014: 2013: 1972: 1941: 1916: 1905: 1904: 1863: 1832: 1807: 1796: 1795: 1761: 1760: 1723: 1686: 1661: 1650: 1649: 1626: 1595: 1570: 1559: 1558: 1529: 1516: 1491: 1480: 1479: 1444: 1431: 1406: 1395: 1394: 1353: 1340: 1315: 1304: 1303: 1269: 1268: 1203: 1202: 1197:000...000 with 1163: 1162: 1138: 1113: 1075: 1069: 1046: 1045: 1006: 993: 992: 964: 963: 944: 943: 912: 892: 863: 858: 853: 852: 824: 823: 789: 788: 671: 666: 665: 628: 627: 624: 622:General results 440: 435: 323: 315:Vampire numbers 289: 262: 112: 96: 58: 40:, parentheses, 18:Friedman number 12: 11: 5: 4676: 4674: 4666: 4665: 4660: 4650: 4649: 4643: 4642: 4640: 4639: 4628: 4625: 4624: 4621: 4620: 4618: 4617: 4611: 4608: 4607: 4601: 4594: 4593: 4590: 4589: 4587: 4586: 4581: 4575: 4572: 4571: 4565: 4558: 4557: 4554: 4553: 4551: 4550: 4548:Sorting number 4545: 4543:Pancake number 4539: 4536: 4535: 4529: 4522: 4521: 4518: 4517: 4515: 4514: 4509: 4503: 4500: 4499: 4493: 4486: 4485: 4482: 4481: 4479: 4478: 4473: 4468: 4462: 4459: 4458: 4455:Binary numbers 4453: 4446: 4445: 4442: 4441: 4438: 4437: 4435: 4434: 4428: 4426: 4422: 4421: 4419: 4418: 4413: 4408: 4403: 4398: 4393: 4388: 4382: 4380: 4376: 4375: 4373: 4372: 4367: 4362: 4357: 4352: 4346: 4344: 4336: 4335: 4333: 4332: 4327: 4322: 4317: 4312: 4307: 4302: 4296: 4294: 4287: 4286: 4284: 4283: 4282: 4281: 4270: 4268: 4265:P-adic numbers 4261: 4260: 4257: 4256: 4254: 4253: 4252: 4251: 4241: 4236: 4231: 4226: 4221: 4216: 4211: 4206: 4200: 4198: 4194: 4193: 4191: 4190: 4184: 4182: 4181:Coding-related 4178: 4177: 4175: 4174: 4169: 4163: 4161: 4157: 4156: 4154: 4153: 4148: 4143: 4138: 4132: 4130: 4121: 4120: 4119: 4118: 4116:Multiplicative 4113: 4102: 4100: 4085: 4084: 4080:Numeral system 4078: 4071: 4070: 4067: 4066: 4064: 4063: 4058: 4053: 4048: 4043: 4038: 4033: 4028: 4023: 4018: 4013: 4008: 4003: 3998: 3993: 3988: 3982: 3979: 3978: 3967: 3960: 3959: 3956: 3955: 3952: 3951: 3949: 3948: 3943: 3937: 3935: 3929: 3928: 3926: 3925: 3920: 3915: 3910: 3904: 3902: 3896: 3895: 3893: 3892: 3887: 3882: 3877: 3872: 3870:Highly totient 3867: 3861: 3859: 3853: 3852: 3850: 3849: 3844: 3838: 3836: 3830: 3829: 3827: 3826: 3821: 3816: 3811: 3806: 3801: 3796: 3791: 3786: 3781: 3776: 3771: 3766: 3761: 3756: 3751: 3746: 3741: 3736: 3731: 3726: 3724:Almost perfect 3721: 3715: 3713: 3703: 3702: 3693: 3686: 3685: 3682: 3681: 3679: 3678: 3673: 3668: 3663: 3658: 3653: 3648: 3643: 3638: 3633: 3628: 3623: 3617: 3614: 3613: 3608: 3601: 3600: 3597: 3596: 3594: 3593: 3588: 3583: 3578: 3572: 3569: 3568: 3563: 3556: 3555: 3552: 3551: 3549: 3548: 3543: 3538: 3533: 3531:Stirling first 3528: 3523: 3518: 3513: 3508: 3503: 3498: 3493: 3488: 3483: 3478: 3473: 3468: 3463: 3458: 3453: 3447: 3444: 3443: 3440: 3433: 3432: 3429: 3428: 3425: 3424: 3421: 3420: 3418: 3417: 3412: 3407: 3401: 3399: 3392: 3386: 3385: 3382: 3381: 3379: 3378: 3372: 3370: 3364: 3363: 3361: 3360: 3355: 3350: 3345: 3340: 3335: 3329: 3327: 3321: 3320: 3318: 3317: 3312: 3307: 3302: 3297: 3291: 3289: 3280: 3274: 3273: 3270: 3269: 3267: 3266: 3261: 3256: 3251: 3246: 3241: 3236: 3231: 3226: 3221: 3215: 3213: 3207: 3206: 3204: 3203: 3198: 3193: 3188: 3183: 3178: 3173: 3168: 3163: 3157: 3155: 3146: 3136: 3135: 3130: 3123: 3122: 3119: 3118: 3116: 3115: 3110: 3105: 3100: 3095: 3090: 3084: 3081: 3080: 3077: 3070: 3069: 3066: 3065: 3063: 3062: 3057: 3052: 3047: 3042: 3036: 3033: 3032: 3029: 3022: 3021: 3018: 3017: 3015: 3014: 3009: 3004: 2999: 2994: 2989: 2984: 2979: 2973: 2970: 2969: 2963: 2956: 2955: 2952: 2951: 2949: 2948: 2943: 2938: 2933: 2928: 2922: 2919: 2918: 2915: 2908: 2907: 2904: 2903: 2901: 2900: 2895: 2890: 2885: 2880: 2875: 2870: 2864: 2861: 2860: 2853: 2846: 2845: 2842: 2841: 2839: 2838: 2833: 2828: 2823: 2818: 2813: 2808: 2803: 2798: 2793: 2788: 2783: 2778: 2773: 2767: 2764: 2763: 2757: 2750: 2749: 2743: 2741: 2740: 2733: 2726: 2718: 2712: 2711: 2710: 2709: 2686: 2659: 2647: 2646: 2645: 2626: 2625:External links 2623: 2620: 2619: 2596: 2581: 2568: 2550: 2549: 2547: 2544: 2527:Roman numerals 2522: 2519: 2502: 2499: 2496: 2476: 2456: 2436: 2416: 2413: 2410: 2407: 2387: 2376: 2375: 2364: 2361: 2358: 2355: 2352: 2349: 2344: 2340: 2330: 2321: 2318: 2315: 2312: 2307: 2303: 2299: 2296: 2293: 2285: 2280: 2276: 2272: 2269: 2247: 2244: 2241: 2230: 2229: 2217: 2214: 2211: 2208: 2205: 2202: 2197: 2193: 2189: 2186: 2183: 2180: 2177: 2174: 2171: 2166: 2162: 2158: 2155: 2152: 2149: 2146: 2141: 2137: 2133: 2130: 2120: 2108: 2105: 2102: 2099: 2096: 2093: 2088: 2084: 2080: 2077: 2074: 2071: 2068: 2065: 2062: 2057: 2053: 2049: 2046: 2043: 2040: 2037: 2032: 2028: 2024: 2021: 2011: 1999: 1996: 1993: 1990: 1987: 1984: 1979: 1975: 1971: 1968: 1965: 1962: 1959: 1956: 1953: 1948: 1944: 1940: 1937: 1934: 1931: 1928: 1923: 1919: 1915: 1912: 1902: 1890: 1887: 1884: 1881: 1878: 1875: 1870: 1866: 1862: 1859: 1856: 1853: 1850: 1847: 1844: 1839: 1835: 1831: 1828: 1825: 1822: 1819: 1814: 1810: 1806: 1803: 1780: 1777: 1774: 1771: 1768: 1757: 1756: 1742: 1739: 1736: 1733: 1730: 1726: 1722: 1719: 1716: 1713: 1710: 1705: 1702: 1699: 1696: 1693: 1689: 1685: 1682: 1679: 1676: 1673: 1668: 1664: 1660: 1657: 1647: 1633: 1629: 1625: 1622: 1619: 1616: 1613: 1608: 1605: 1602: 1598: 1594: 1591: 1588: 1585: 1582: 1577: 1573: 1569: 1566: 1556: 1544: 1541: 1536: 1532: 1528: 1523: 1519: 1515: 1512: 1509: 1506: 1503: 1498: 1494: 1490: 1487: 1477: 1465: 1462: 1459: 1456: 1451: 1447: 1443: 1438: 1434: 1430: 1427: 1424: 1421: 1418: 1413: 1409: 1405: 1402: 1392: 1380: 1377: 1374: 1371: 1368: 1365: 1360: 1356: 1352: 1347: 1343: 1339: 1336: 1333: 1330: 1327: 1322: 1318: 1314: 1311: 1288: 1285: 1282: 1279: 1276: 1265: 1264: 1257: 1250: 1216: 1213: 1210: 1170: 1159: 1158: 1145: 1141: 1137: 1134: 1131: 1128: 1125: 1120: 1116: 1112: 1109: 1106: 1102: 1097: 1093: 1090: 1087: 1084: 1081: 1078: 1072: 1068: 1065: 1062: 1059: 1056: 1053: 1028: 1024: 1021: 1018: 1015: 1012: 1009: 1003: 1000: 977: 974: 971: 951: 940: 939: 928: 925: 919: 915: 910: 907: 902: 899: 895: 891: 886: 881: 878: 875: 870: 866: 862: 837: 834: 831: 796: 785: 784: 773: 770: 767: 764: 761: 758: 755: 752: 749: 746: 743: 740: 737: 734: 731: 728: 725: 722: 719: 716: 713: 710: 707: 704: 701: 698: 695: 692: 689: 686: 683: 678: 674: 650: 647: 644: 641: 638: 635: 623: 620: 617: 616: 613: 609: 608: 601: 597: 596: 585: 581: 580: 577: 573: 572: 569: 565: 564: 561: 557: 556: 549: 545: 544: 538: 534: 533: 526: 522: 521: 515: 511: 510: 505:, 1232, 1241, 499: 495: 494: 487: 483: 482: 479: 475: 474: 463: 459: 458: 455: 438: 434: 431: 322: 319: 300: 299: 273: 272: 247: 246: 243: 240: 237: 234: 231: 228: 225: 221: 220: 217: 214: 211: 208: 205: 202: 199: 195: 194: 191: 188: 185: 182: 179: 176: 173: 169: 168: 165: 162: 159: 156: 153: 150: 147: 143: 142: 139: 136: 133: 130: 127: 124: 121: 111: 108: 107: 106: 84:Friedman prime 73:Erich Friedman 69: 68: 42:exponentiation 30:numeral system 13: 10: 9: 6: 4: 3: 2: 4675: 4664: 4661: 4659: 4656: 4655: 4653: 4638: 4634: 4630: 4629: 4626: 4616: 4613: 4612: 4609: 4604: 4599: 4595: 4585: 4582: 4580: 4577: 4576: 4573: 4568: 4563: 4559: 4549: 4546: 4544: 4541: 4540: 4537: 4532: 4527: 4523: 4513: 4510: 4508: 4505: 4504: 4501: 4497: 4491: 4487: 4477: 4474: 4472: 4469: 4467: 4464: 4463: 4460: 4456: 4451: 4447: 4433: 4430: 4429: 4427: 4423: 4417: 4414: 4412: 4409: 4407: 4406:Polydivisible 4404: 4402: 4399: 4397: 4394: 4392: 4389: 4387: 4384: 4383: 4381: 4377: 4371: 4368: 4366: 4363: 4361: 4358: 4356: 4353: 4351: 4348: 4347: 4345: 4342: 4337: 4331: 4328: 4326: 4323: 4321: 4318: 4316: 4313: 4311: 4308: 4306: 4303: 4301: 4298: 4297: 4295: 4292: 4288: 4280: 4277: 4276: 4275: 4272: 4271: 4269: 4266: 4262: 4250: 4247: 4246: 4245: 4242: 4240: 4237: 4235: 4232: 4230: 4227: 4225: 4222: 4220: 4217: 4215: 4212: 4210: 4207: 4205: 4202: 4201: 4199: 4195: 4189: 4186: 4185: 4183: 4179: 4173: 4170: 4168: 4165: 4164: 4162: 4160:Digit product 4158: 4152: 4149: 4147: 4144: 4142: 4139: 4137: 4134: 4133: 4131: 4129: 4125: 4117: 4114: 4112: 4109: 4108: 4107: 4104: 4103: 4101: 4099: 4094: 4090: 4086: 4081: 4076: 4072: 4062: 4059: 4057: 4054: 4052: 4049: 4047: 4044: 4042: 4039: 4037: 4034: 4032: 4029: 4027: 4024: 4022: 4019: 4017: 4014: 4012: 4009: 4007: 4004: 4002: 3999: 3997: 3996:ErdƑs–Nicolas 3994: 3992: 3989: 3987: 3984: 3983: 3980: 3975: 3971: 3965: 3961: 3947: 3944: 3942: 3939: 3938: 3936: 3934: 3930: 3924: 3921: 3919: 3916: 3914: 3911: 3909: 3906: 3905: 3903: 3901: 3897: 3891: 3888: 3886: 3883: 3881: 3878: 3876: 3873: 3871: 3868: 3866: 3863: 3862: 3860: 3858: 3854: 3848: 3845: 3843: 3840: 3839: 3837: 3835: 3831: 3825: 3822: 3820: 3817: 3815: 3814:Superabundant 3812: 3810: 3807: 3805: 3802: 3800: 3797: 3795: 3792: 3790: 3787: 3785: 3782: 3780: 3777: 3775: 3772: 3770: 3767: 3765: 3762: 3760: 3757: 3755: 3752: 3750: 3747: 3745: 3742: 3740: 3737: 3735: 3732: 3730: 3727: 3725: 3722: 3720: 3717: 3716: 3714: 3712: 3708: 3704: 3700: 3696: 3691: 3687: 3677: 3674: 3672: 3669: 3667: 3664: 3662: 3659: 3657: 3654: 3652: 3649: 3647: 3644: 3642: 3639: 3637: 3634: 3632: 3629: 3627: 3624: 3622: 3619: 3618: 3615: 3611: 3606: 3602: 3592: 3589: 3587: 3584: 3582: 3579: 3577: 3574: 3573: 3570: 3566: 3561: 3557: 3547: 3544: 3542: 3539: 3537: 3534: 3532: 3529: 3527: 3524: 3522: 3519: 3517: 3514: 3512: 3509: 3507: 3504: 3502: 3499: 3497: 3494: 3492: 3489: 3487: 3484: 3482: 3479: 3477: 3474: 3472: 3469: 3467: 3464: 3462: 3459: 3457: 3454: 3452: 3449: 3448: 3445: 3438: 3434: 3416: 3413: 3411: 3408: 3406: 3403: 3402: 3400: 3396: 3393: 3391: 3390:4-dimensional 3387: 3377: 3374: 3373: 3371: 3369: 3365: 3359: 3356: 3354: 3351: 3349: 3346: 3344: 3341: 3339: 3336: 3334: 3331: 3330: 3328: 3326: 3322: 3316: 3313: 3311: 3308: 3306: 3303: 3301: 3300:Centered cube 3298: 3296: 3293: 3292: 3290: 3288: 3284: 3281: 3279: 3278:3-dimensional 3275: 3265: 3262: 3260: 3257: 3255: 3252: 3250: 3247: 3245: 3242: 3240: 3237: 3235: 3232: 3230: 3227: 3225: 3222: 3220: 3217: 3216: 3214: 3212: 3208: 3202: 3199: 3197: 3194: 3192: 3189: 3187: 3184: 3182: 3179: 3177: 3174: 3172: 3169: 3167: 3164: 3162: 3159: 3158: 3156: 3154: 3150: 3147: 3145: 3144:2-dimensional 3141: 3137: 3133: 3128: 3124: 3114: 3111: 3109: 3106: 3104: 3101: 3099: 3096: 3094: 3091: 3089: 3088:Nonhypotenuse 3086: 3085: 3082: 3075: 3071: 3061: 3058: 3056: 3053: 3051: 3048: 3046: 3043: 3041: 3038: 3037: 3034: 3027: 3023: 3013: 3010: 3008: 3005: 3003: 3000: 2998: 2995: 2993: 2990: 2988: 2985: 2983: 2980: 2978: 2975: 2974: 2971: 2966: 2961: 2957: 2947: 2944: 2942: 2939: 2937: 2934: 2932: 2929: 2927: 2924: 2923: 2920: 2913: 2909: 2899: 2896: 2894: 2891: 2889: 2886: 2884: 2881: 2879: 2876: 2874: 2871: 2869: 2866: 2865: 2862: 2857: 2851: 2847: 2837: 2834: 2832: 2829: 2827: 2826:Perfect power 2824: 2822: 2819: 2817: 2816:Seventh power 2814: 2812: 2809: 2807: 2804: 2802: 2799: 2797: 2794: 2792: 2789: 2787: 2784: 2782: 2779: 2777: 2774: 2772: 2769: 2768: 2765: 2760: 2755: 2751: 2747: 2739: 2734: 2732: 2727: 2725: 2720: 2719: 2716: 2707: 2703: 2699: 2695: 2694: 2693: 2687: 2682: 2677: 2673: 2669: 2665: 2660: 2656: 2652: 2648: 2644: 2640: 2637: 2636: 2635: 2629: 2628: 2624: 2615: 2609: 2607: 2605: 2603: 2601: 2597: 2592: 2585: 2582: 2578: 2572: 2569: 2565: 2561: 2555: 2552: 2545: 2543: 2540: 2535: 2531: 2528: 2520: 2518: 2516: 2500: 2497: 2494: 2474: 2454: 2434: 2414: 2411: 2408: 2405: 2385: 2362: 2359: 2356: 2353: 2350: 2347: 2342: 2328: 2319: 2316: 2310: 2305: 2301: 2297: 2294: 2291: 2283: 2278: 2274: 2270: 2267: 2260: 2259: 2258: 2245: 2242: 2239: 2232:and for base 2215: 2212: 2209: 2206: 2203: 2200: 2195: 2187: 2184: 2181: 2178: 2175: 2169: 2164: 2160: 2156: 2153: 2150: 2147: 2144: 2139: 2135: 2131: 2128: 2121: 2106: 2103: 2100: 2097: 2094: 2091: 2086: 2078: 2075: 2072: 2069: 2066: 2060: 2055: 2051: 2047: 2044: 2041: 2038: 2035: 2030: 2026: 2022: 2019: 2012: 1997: 1994: 1991: 1988: 1985: 1982: 1977: 1969: 1966: 1963: 1960: 1957: 1951: 1946: 1942: 1938: 1935: 1932: 1929: 1926: 1921: 1917: 1913: 1910: 1903: 1888: 1885: 1882: 1879: 1876: 1873: 1868: 1860: 1857: 1854: 1851: 1848: 1842: 1837: 1833: 1829: 1826: 1823: 1820: 1817: 1812: 1808: 1804: 1801: 1794: 1793: 1792: 1778: 1775: 1772: 1769: 1766: 1737: 1734: 1731: 1720: 1717: 1714: 1708: 1703: 1700: 1697: 1694: 1691: 1687: 1683: 1680: 1677: 1674: 1671: 1666: 1662: 1658: 1655: 1648: 1631: 1623: 1620: 1617: 1611: 1606: 1603: 1600: 1596: 1592: 1589: 1586: 1583: 1580: 1575: 1571: 1567: 1564: 1557: 1542: 1539: 1534: 1530: 1526: 1521: 1517: 1513: 1510: 1507: 1504: 1501: 1496: 1492: 1488: 1485: 1478: 1463: 1460: 1457: 1454: 1449: 1445: 1441: 1436: 1432: 1428: 1425: 1422: 1419: 1416: 1411: 1407: 1403: 1400: 1393: 1378: 1375: 1372: 1369: 1366: 1363: 1358: 1354: 1350: 1345: 1341: 1337: 1334: 1331: 1328: 1325: 1320: 1316: 1312: 1309: 1302: 1301: 1300: 1286: 1283: 1280: 1277: 1274: 1262: 1258: 1255: 1251: 1248: 1244: 1243: 1242: 1240: 1236: 1234: 1230: 1214: 1211: 1208: 1200: 1196: 1192: 1188: 1184: 1168: 1143: 1139: 1135: 1132: 1129: 1126: 1123: 1118: 1114: 1110: 1107: 1104: 1100: 1095: 1088: 1085: 1082: 1076: 1070: 1066: 1063: 1060: 1057: 1054: 1051: 1044: 1043: 1042: 1026: 1019: 1016: 1013: 1007: 1001: 998: 989: 975: 972: 969: 949: 926: 923: 917: 913: 908: 905: 900: 897: 893: 889: 884: 876: 873: 868: 864: 851: 850: 849: 835: 832: 829: 820: 818: 814: 810: 794: 768: 765: 762: 759: 753: 750: 747: 744: 741: 738: 735: 732: 729: 726: 723: 717: 714: 711: 708: 705: 702: 696: 693: 690: 687: 684: 681: 676: 672: 664: 663: 662: 648: 645: 642: 639: 636: 633: 621: 614: 611: 610: 606: 602: 599: 598: 594: 590: 586: 583: 582: 578: 575: 574: 570: 567: 566: 562: 559: 558: 554: 550: 547: 546: 542: 539: 536: 535: 531: 527: 524: 523: 519: 516: 513: 512: 508: 504: 500: 497: 496: 492: 488: 485: 484: 480: 477: 476: 472: 468: 464: 461: 460: 456: 453: 452: 449: 446: 444: 432: 430: 428: 424: 420: 416: 412: 408: 404: 400: 396: 392: 388: 384: 380: 376: 372: 368: 364: 360: 356: 352: 348: 344: 340: 336: 332: 328: 320: 318: 316: 312: 309: 305: 297: 292: 286: 285: 284: 282: 278: 270: 265: 259: 258: 257: 254: 244: 241: 238: 235: 232: 229: 226: 223: 222: 218: 215: 212: 209: 206: 203: 200: 197: 196: 192: 189: 186: 183: 180: 177: 174: 171: 170: 166: 163: 160: 157: 154: 151: 148: 145: 144: 140: 137: 134: 131: 128: 125: 122: 119: 118: 115: 109: 104: 99: 93: 92: 91: 89: 85: 80: 78: 74: 66: 61: 55: 54: 53: 51: 47: 46:concatenation 43: 39: 35: 31: 27: 23: 19: 4431: 4370:Transposable 4234:Narcissistic 4141:Digital root 4061:Super-Poulet 4021:Jordan–PĂłlya 3970:prime factor 3875:Noncototient 3842:Almost prime 3824:Superperfect 3799:Refactorable 3794:Quasiperfect 3769:Hyperperfect 3610:Pseudoprimes 3581:Wall–Sun–Sun 3516:Ordered Bell 3486:Fuss–Catalan 3398:non-centered 3348:Dodecahedral 3325:non-centered 3211:non-centered 3113:Wolstenholme 2858:× 2 ± 1 2855: 2854:Of the form 2821:Eighth power 2801:Fourth power 2705: 2701: 2671: 2667: 2654: 2614:"Math Magic" 2584: 2571: 2563: 2559: 2554: 2536: 2532: 2524: 2377: 2231: 1791:the numbers 1758: 1299:the numbers 1266: 1237: 1198: 1194: 1190: 1186: 1182: 1160: 990: 941: 821: 816: 812: 808: 786: 625: 604: 592: 588: 552: 540: 529: 517: 506: 502: 490: 470: 466: 447: 436: 426: 422: 418: 414: 410: 406: 402: 398: 394: 390: 386: 382: 378: 374: 370: 366: 362: 358: 354: 350: 346: 342: 338: 334: 330: 326: 324: 313: 307: 303: 301: 280: 276: 274: 252: 250: 113: 83: 81: 70: 17: 15: 4391:Extravagant 4386:Equidigital 4341:permutation 4300:Palindromic 4274:Automorphic 4172:Sum-product 4151:Sum-product 4106:Persistence 4001:ErdƑs–Woods 3923:Untouchable 3804:Semiperfect 3754:Hemiperfect 3415:Tesseractic 3353:Icosahedral 3333:Tetrahedral 3264:Dodecagonal 2965:Recursively 2836:Prime power 2811:Sixth power 2806:Fifth power 2786:Power of 10 2744:Classes of 2228:in base 10, 595:, 173, ... 433:Other bases 141:expression 135:expression 129:expression 123:expression 28:in a given 26:represented 4652:Categories 4603:Graphemics 4476:Pernicious 4330:Undulating 4305:Pandigital 4279:Trimorphic 3880:Nontotient 3729:Arithmetic 3343:Octahedral 3244:Heptagonal 3234:Pentagonal 3219:Triangular 3060:SierpiƄski 2982:Jacobsthal 2781:Power of 3 2776:Power of 2 2546:References 2119:in base 9, 2010:in base 8, 1901:in base 7, 587:121, 128, 551:121, 134, 528:121, 143, 4360:Parasitic 4209:Factorion 4136:Digit sum 4128:Digit sum 3946:Fortunate 3933:Primorial 3847:Semiprime 3784:Practical 3749:Descartes 3744:Deficient 3734:Betrothed 3576:Wieferich 3405:Pentatope 3368:pyramidal 3259:Decagonal 3254:Nonagonal 3249:Octagonal 3239:Hexagonal 3098:Practical 3045:Congruent 2977:Fibonacci 2941:Loeschian 2363:… 2298:× 2271:× 2216:… 2185:− 2157:× 2132:× 2107:… 2076:− 2048:× 2023:× 1998:… 1967:− 1939:× 1914:× 1889:… 1858:− 1830:× 1805:× 1776:≤ 1770:≤ 1759:for base 1755:in base 6 1701:− 1695:× 1684:× 1659:× 1646:in base 5 1621:× 1593:× 1568:× 1555:in base 4 1514:× 1489:× 1476:in base 3 1429:× 1404:× 1391:in base 2 1364:− 1338:× 1313:× 1284:≤ 1278:≤ 1261:repdigits 1124:− 1086:− 1017:− 973:− 709:− 646:− 4432:Friedman 4365:Primeval 4310:Repdigit 4267:-related 4214:Kaprekar 4188:Meertens 4111:Additive 4098:dynamics 4006:Friendly 3918:Sociable 3908:Amicable 3719:Abundant 3699:dynamics 3521:Schröder 3511:Narayana 3481:Eulerian 3471:Delannoy 3466:Dedekind 3287:centered 3153:centered 3040:Amenable 2997:Narayana 2987:Leonardo 2883:Mersenne 2831:Powerful 2771:Achilles 2427:, where 1675:25352411 1329:11111111 1239:Repdigit 1227:, or in 991:In base 822:In base 626:In base 333:, where 24:, which 4605:related 4569:related 4533:related 4531:Sorting 4416:Vampire 4401:Harshad 4343:related 4315:Repunit 4229:Lychrel 4204:Dudeney 4056:StĂžrmer 4051:Sphenic 4036:Regular 3974:divisor 3913:Perfect 3809:Sublime 3779:Perfect 3506:Motzkin 3461:Catalan 3002:Padovan 2936:Leyland 2931:Idoneal 2926:Hilbert 2898:Woodall 1584:2443111 1420:1101221 1254:base 10 1233:base 10 1229:base 10 465:11001, 294:in the 291:A252483 267:in the 264:A080035 138:number 132:number 126:number 120:number 101:in the 98:A112419 63:in the 60:A036057 22:integer 4471:Odious 4396:Frugal 4350:Cyclic 4339:Digit- 4046:Smooth 4031:Pronic 3991:Cyclic 3968:Other 3941:Euclid 3591:Wilson 3565:Primes 3224:Square 3093:Polite 3055:Riesel 3050:Knödel 3012:Perrin 2893:Thabit 2878:Fermat 2868:Cullen 2791:Square 2759:Powers 2655:Github 2288:15AA51 2148:161051 2039:162151 1930:163251 1821:164351 1505:310233 1247:base 8 607:, ... 509:, ... 471:111111 369:, and 245:(4−2) 187:(3+4) 161:(8+9) 44:, and 34:digits 20:is an 4512:Prime 4507:Lucky 4496:sieve 4425:Other 4411:Smith 4291:Digit 4249:Happy 4224:Keith 4197:Other 4041:Rough 4011:Giuga 3476:Euler 3338:Cubic 2992:Lucas 2888:Proth 501:121, 489:121, 467:11011 409:< 405:when 242:1024 227:6×21 216:1022 207:3×51 167:8×86 88:prime 4466:Evil 4146:Self 4096:and 3986:Blum 3697:and 3501:Lobb 3456:Cake 3451:Bell 3201:Star 3108:Ulam 3007:Pell 2796:Cube 2689:OEIS 2631:OEIS 2487:and 2447:and 2243:> 1359:1000 1346:1111 1321:1111 1181:as 2 833:> 819:1). 807:as 1 507:1242 454:base 421:and 353:and 296:OEIS 281:nice 277:nice 269:OEIS 253:nice 236:625 230:216 224:126 219:2−2 213:7+4 210:347 204:153 198:125 193:3+7 190:736 184:343 178:128 172:121 164:688 158:289 155:2−1 152:127 103:OEIS 65:OEIS 4584:Ban 3972:or 3491:Lah 2676:doi 2672:161 2641:in 2564:161 1450:101 1437:102 1412:102 661:, 612:16 605:336 600:15 593:144 589:135 584:14 576:13 568:12 560:11 553:314 530:144 503:224 491:123 389:or 175:11 146:25 4654:: 2704:. 2700:. 2670:. 2666:. 2653:. 2599:^ 2562:, 2317:10 2306:50 2302:10 2279:50 2275:10 2246:10 2176:10 2165:60 2161:10 2140:60 2136:10 2067:10 2056:60 2052:10 2031:60 2027:10 1958:10 1947:60 1943:10 1922:60 1918:10 1849:10 1838:60 1834:10 1813:60 1809:10 1779:10 1688:10 1667:13 1663:10 1632:11 1597:10 1576:13 1572:10 1531:33 1522:20 1518:10 1497:20 1493:10 1433:10 1408:10 1355:10 1342:10 1317:10 1235:. 1185:= 1041:, 848:, 815:× 811:= 809:mk 591:, 548:9 541:33 537:8 525:7 518:24 514:6 498:5 486:4 478:3 469:, 462:2 429:. 425:/ 417:− 401:+ 399:mb 393:× 385:+ 377:= 373:+ 371:mb 365:= 361:+ 359:mb 341:, 329:+ 327:mb 298:). 275:A 271:). 251:A 239:5 233:6 201:5 181:2 149:5 105:). 82:A 67:). 16:A 2856:a 2737:e 2730:t 2723:v 2684:. 2678:: 2616:. 2593:. 2579:. 2501:1 2498:+ 2495:b 2475:b 2455:q 2435:p 2415:q 2412:+ 2409:n 2406:p 2386:n 2360:+ 2357:0 2354:+ 2351:0 2348:+ 2343:5 2339:) 2334:A 2329:/ 2324:A 2320:+ 2314:( 2311:+ 2295:n 2292:= 2284:+ 2268:n 2240:b 2213:+ 2210:0 2207:+ 2204:0 2201:+ 2196:5 2192:) 2188:0 2182:1 2179:+ 2173:( 2170:+ 2154:n 2151:= 2145:+ 2129:n 2104:+ 2101:0 2098:+ 2095:0 2092:+ 2087:5 2083:) 2079:1 2073:2 2070:+ 2064:( 2061:+ 2045:n 2042:= 2036:+ 2020:n 1995:+ 1992:0 1989:+ 1986:0 1983:+ 1978:5 1974:) 1970:2 1964:3 1961:+ 1955:( 1952:+ 1936:n 1933:= 1927:+ 1911:n 1886:+ 1883:0 1880:+ 1877:0 1874:+ 1869:5 1865:) 1861:3 1855:4 1852:+ 1846:( 1843:+ 1827:n 1824:= 1818:+ 1802:n 1773:b 1767:7 1741:) 1738:4 1735:+ 1732:3 1729:( 1725:) 1721:2 1718:+ 1715:5 1712:( 1709:+ 1704:1 1698:5 1692:2 1681:n 1678:= 1672:+ 1656:n 1628:) 1624:3 1618:2 1615:( 1612:+ 1607:4 1604:+ 1601:4 1590:n 1587:= 1581:+ 1565:n 1543:0 1540:+ 1535:3 1527:+ 1511:n 1508:= 1502:+ 1486:n 1464:0 1461:+ 1458:0 1455:+ 1446:2 1442:+ 1426:n 1423:= 1417:+ 1401:n 1379:0 1376:+ 1373:0 1370:+ 1367:1 1351:+ 1335:n 1332:= 1326:+ 1310:n 1287:6 1281:b 1275:2 1215:5 1212:= 1209:k 1199:n 1195:k 1191:k 1187:k 1183:k 1169:b 1144:2 1140:k 1136:= 1133:k 1130:+ 1127:k 1119:2 1115:k 1111:= 1108:k 1105:+ 1101:) 1096:2 1092:) 1089:1 1083:k 1080:( 1077:k 1071:( 1067:2 1064:= 1061:k 1058:+ 1055:b 1052:2 1027:2 1023:) 1020:1 1014:k 1011:( 1008:k 1002:= 999:b 976:1 970:n 950:b 927:1 924:+ 918:n 914:b 909:2 906:+ 901:n 898:2 894:b 890:= 885:2 880:) 877:1 874:+ 869:n 865:b 861:( 836:2 830:b 817:m 813:k 795:b 772:) 769:1 766:+ 763:b 760:m 757:( 754:k 751:= 748:k 745:+ 742:k 739:b 736:m 733:= 730:k 727:+ 724:b 721:) 718:m 715:+ 712:m 706:k 703:m 700:( 697:= 694:k 691:+ 688:b 685:m 682:+ 677:2 673:b 649:m 643:k 640:m 637:= 634:b 439:2 427:n 423:m 419:n 415:m 411:b 407:n 403:n 395:n 391:m 387:n 383:m 379:n 375:n 367:m 363:n 355:n 351:m 347:b 343:n 339:m 335:b 331:n 308:n 304:n

Index

integer
represented
numeral system
digits
additive inverses
exponentiation
concatenation
decimal numeral system
A036057
OEIS
Erich Friedman
Stetson University
prime
A112419
OEIS
A080035
OEIS
A252483
OEIS
Vampire numbers
binary numeral system
base 10
base 10
Repdigit
base 8
base 10
repdigits
Dirichlet's theorem on arithmetic progressions
Roman numerals
positional notation

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