Knowledge (XXG)

Square number

Source 📝

882: 2031: 27: 84: 4841: 1774: 2090:. The difference between any two odd perfect squares is a multiple of 8. The difference between 1 and any higher odd perfect square always is eight times a triangular number, while the difference between 9 and any higher odd perfect square is eight times a triangular number minus eight. Since all triangular numbers have an odd factor, but no two values of 2250:
If the number ends in 5, its square will end in 5; similarly for ending in 25, 625, 0625, 90625, ... 8212890625, etc. If the number ends in 6, its square will end in 6, similarly for ending in 76, 376, 9376, 09376, ... 1787109376. For example, the square of 55376 is 3066501376, both ending in
1749: 2360:. An analogous pattern applies for the last 3 digits around multiples of 250, and so on. As a consequence, of the 100 possible last 2 digits, only 22 of them occur among square numbers (since 00 and 25 are repeated). 346: 1434:
is definitely not square. Repeating the divisions of the previous sentence, one concludes that every prime must divide a given perfect square an even number of times (including possibly 0 times). Thus, the number
2021: 1377:
Similar rules can be given for other bases, or for earlier digits (the tens instead of the units digit, for example). All such rules can be proved by checking a fixed number of cases and using
1785:: if a body falling from rest covers one unit of distance in the first arbitrary time interval, it covers 3, 5, 7, etc., units of distance in subsequent time intervals of the same length. From 1571: 872: 379: 2358: 1840: 1259: 1111: 1553: 2943: 409: 249: 2270:
In base 10, the last two digits of square numbers follow a repeating pattern mirrored symmetrical around multiples of 25. In the example of 24 and 26, both 1 off from 25,
1147: 881: 1917: 1042: 1440: 1013: 802:
as can be seen in the above pictures, where a square results from the previous one by adding an odd number of points (shown in magenta). The formula follows:
2578: 2389: 2508: 2264: 1762: 1298:
states that any positive integer can be written as the sum of four or fewer perfect squares. Three squares are not sufficient for numbers of the form
434: 291:
numbers are included, then a square is the ratio of two square integers, and, conversely, the ratio of two square integers is a square, for example,
2936: 1292:
of positive divisors. An integer root is the only divisor that pairs up with itself to yield the square number, while other divisors come in pairs.
659:. Equivalently, it is possible to count square numbers by adding together the last square, the last square's root, and the current root, that is, 294: 2482: 1922: 1769:
0, 1, 5, 14, 30, 55, 91, 140, 204, 285, 385, 506, 650, 819, 1015, 1240, 1496, 1785, 2109, 2470, 2870, 3311, 3795, 4324, 4900, 5525, 6201...
48: 3743: 2929: 777: 760: 2371: 743: 726: 709: 3738: 1288:
Another property of a square number is that (except 0) it has an odd number of positive divisors, while other natural numbers have an
3753: 3733: 4895: 2541: 2406: 1364:
if a number is divisible both by 2 and by 3 (that is, divisible by 6), its square ends in 0, and its preceding digit must be 0 or 3;
70: 2030: 1781:
The sum of the first odd integers, beginning with one, is a perfect square: 1, 1 + 3, 1 + 3 + 5, 1 + 3 + 5 + 7, etc. This explains
1295: 805: 4446: 4026: 2383: 1782: 187:
points, the points can be arranged in rows as a square each side of which has the same number of points as the square root of
4865: 3748: 2571: 4532: 1191: 1370:
if a number is divisible by 2, but not by 3, its square ends in 4, and its preceding digit must be 0, 1, 4, 5, 8, or 9; and
3848: 1047: 4198: 3517: 3310: 2756: 4233: 4203: 3878: 3868: 1188:
More generally, the difference of the squares of two numbers is the product of their sum and their difference. That is,
4374: 3788: 3522: 3502: 2761: 2741: 4064: 41: 35: 4228: 4875: 4323: 3946: 3703: 3512: 3494: 3388: 3378: 3368: 2751: 2733: 2632: 2622: 2612: 4208: 4870: 4451: 3996: 3617: 3403: 3398: 3393: 3383: 3360: 2856: 2647: 2642: 2637: 2627: 2604: 2564: 2087: 1487: 1282: 1262: 354: 1788: 52: 3436: 2436: 2281: 3693: 4890: 4562: 4527: 4313: 4223: 4097: 4072: 3981: 3971: 3583: 3565: 3485: 2822: 2799: 2724: 1883: 1752: 1744:{\displaystyle \sum _{n=0}^{N}n^{2}=0^{2}+1^{2}+2^{2}+3^{2}+4^{2}+\cdots +N^{2}={\frac {N(N+1)(2N+1)}{6}}.} 1367:
if a number is divisible neither by 2 nor by 3, its square ends in 1, and its preceding digit must be even;
4885: 4822: 4092: 3966: 3597: 3373: 3153: 3080: 2836: 2617: 1373:
if a number is not divisible by 2, but by 3, its square ends in 9, and its preceding digit must be 0 or 6.
1278: 4077: 3931: 3858: 3013: 2891: 1525: 4786: 4426: 1867:, and the distance from the starting point are consecutive squares for integer values of time elapsed. 388: 83: 4719: 4613: 4577: 4318: 4041: 4021: 3838: 3507: 3295: 3267: 2746: 1289: 799: 221: 4441: 4305: 4300: 4268: 4031: 4006: 4001: 3976: 3906: 3902: 3833: 3723: 3555: 3351: 3320: 2789: 2595: 2400: 2034: 1319: 1307: 259: 4840: 1120: 4844: 4598: 4593: 4507: 4481: 4379: 4358: 4130: 4011: 3961: 3883: 3853: 3793: 3560: 3540: 3471: 3184: 2817: 2794: 2710: 2430: 2418: 2256: 2053: 1378: 200: 3728: 2083:
is always even. In other words, all odd square numbers have a remainder of 1 when divided by 8.
4880: 4738: 4683: 4537: 4512: 4486: 4263: 3941: 3936: 3863: 3843: 3828: 3550: 3532: 3451: 3441: 3426: 3204: 3189: 2784: 2771: 2690: 2680: 2670: 2537: 2478: 2424: 1274: 2472: 1345:
if the last digit of a number is 4 or 6, its square ends in an odd digit followed by a 6; and
4774: 4567: 4153: 4125: 4115: 4107: 3991: 3956: 3951: 3918: 3612: 3575: 3466: 3461: 3456: 3446: 3418: 3305: 3257: 3252: 3209: 3148: 2851: 2809: 2705: 2700: 2695: 2685: 2662: 2458: 2395: 112: 1895: 4750: 4639: 4572: 4498: 4421: 4395: 4213: 3926: 3783: 3718: 3688: 3678: 3673: 3339: 3247: 3194: 3038: 2978: 2587: 1342:
if the last digit of a number is 3 or 7, its square ends in an even digit followed by a 9;
1339:
if the last digit of a number is 2 or 8, its square ends in an even digit followed by a 4;
1336:
if the last digit of a number is 1 or 9, its square ends in an even digit followed by a 1;
1018: 288: 192: 88: 992: 4755: 4623: 4608: 4472: 4436: 4411: 4287: 4258: 4243: 4120: 4016: 3986: 3713: 3668: 3545: 3143: 3138: 3133: 3105: 3090: 3003: 2988: 2966: 2953: 2779: 2377: 1875: 1558: 644:
The difference between any perfect square and its predecessor is given by the identity
412: 196: 145: 116: 4859: 4678: 4662: 4603: 4557: 4253: 4238: 4148: 3873: 3300: 3262: 3219: 3100: 3085: 3075: 3033: 3023: 2901: 1447: 2146:
and represents digits before 25. For example, the square of 65 can be calculated by
1450:
of large numbers. Instead of testing for divisibility, test for squarity: for given
4714: 4703: 4618: 4456: 4431: 4348: 4248: 4218: 4193: 4177: 4082: 4049: 3798: 3772: 3683: 3622: 3199: 3095: 3028: 3008: 2983: 2906: 2861: 2412: 1385: 1357: 1150: 211: 2094:
differ by an amount containing an odd factor, the only perfect square of the form
2551: 1306:. A positive integer can be represented as a sum of two squares precisely if its 4673: 4548: 4353: 3817: 3708: 3663: 3658: 3408: 3315: 3214: 3043: 3018: 2993: 2896: 2652: 2526: 2498: 1773: 215: 207: 166: 119:
of some integer with itself. For example, 9 is a square number, since it equals
96: 776: 759: 4810: 4791: 4087: 3698: 1889:
All fourth powers, sixth powers, eighth powers and so on are perfect squares.
742: 725: 708: 284: 2921: 4416: 4343: 4335: 4140: 4054: 3172: 2876: 1498:
divides 9991. This test is deterministic for odd divisors in the range from
909: 287:
one. The concept of square can be extended to some other number systems. If
1329:, a square number can end only with digits 0, 1, 4, 5, 6 or 9, as follows: 2386: – Product of sums of four squares expressed as a sum of four squares 4517: 2530: 1360:
can end only with prime digits or 1), that is, 0, 1, 4 or 9, as follows:
943:
th square number can be calculated from the previous two by doubling the
341:{\displaystyle \textstyle {\frac {4}{9}}=\left({\frac {2}{3}}\right)^{2}} 2471:
Olenick, Richard P.; Apostol, Tom M.; Goodstein, David L. (2008-01-14).
4522: 4181: 1353: 1326: 255: 108: 2374: – Expression of a product of sums of squares as a sum of squares 1356:, a square number can end only with square digits (like in base 12, a 2439: – Integer that is both a perfect square and a triangular number 2503:"Sequence A003226 (Automorphic numbers: n^2 ends with n.)" 2556: 2392: – Condition under which an odd prime is a sum of two squares 2029: 880: 82: 2041:
Squares of even numbers are even, and are divisible by 4, since
162: 4808: 4772: 4736: 4700: 4660: 4285: 4174: 3900: 3815: 3770: 3647: 3337: 3284: 3236: 3170: 3122: 3060: 2964: 2925: 2560: 20: 916:
th square number can be computed from the previous square by
2427: – Integer that is a perfect square modulo some integer 2502: 2474:
The Mechanical Universe: Introduction to Mechanics and Heat
2260: 1757: 429: 2403: – Greatest integer less than or equal to square root 1348:
if the last digit of a number is 5, its square ends in 25.
1333:
if the last digit of a number is 0, its square ends in 00;
1265:, which can be useful for mental arithmetic: for example, 2052:. Squares of odd numbers are odd, and are congruent to 1 1855:(acceleration due to gravity without air resistance); so 1174:
on the right side of the equation above, it follows that
2016:{\displaystyle (T_{n})^{2}+(T_{n+1})^{2}=T_{(n+1)^{2}}} 912:
methods for computing square numbers. For example, the
2284: 1808: 1777:
Proof without words for the sum of odd numbers theorem
979:
2 × 5 − 4 + 2 = 2 × 25 − 16 + 2 = 50 − 16 + 2 = 36 = 6
298: 1925: 1898: 1791: 1574: 1528: 1273:. A square number is also the sum of two consecutive 1194: 1123: 1050: 1021: 995: 808: 391: 357: 297: 224: 214:. A non-negative integer is a square number when its 161:
number comes from the name of the shape. The unit of
2548:
Amazing Properties of Squares and Their Calculations
1486:. (This is an application of the factorization of a 4632: 4586: 4546: 4497: 4471: 4404: 4388: 4367: 4334: 4299: 4139: 4106: 4063: 4040: 3917: 3605: 3596: 3574: 3531: 3493: 3484: 3417: 3359: 3350: 2884: 2874: 2844: 2835: 2808: 2770: 2732: 2723: 2661: 2603: 2594: 2536:. New York: Springer-Verlag, pp. 30–32, 1996. 2037:
that all centered octagonal numbers are odd squares
1446:Squarity testing can be used as alternative way in 2352: 2015: 1911: 1834: 1743: 1547: 1253: 1141: 1105: 1036: 1007: 866: 689:is a square number if and only if one can arrange 403: 373: 340: 243: 1277:. The sum of two consecutive square numbers is a 1178:is the only prime number one less than a square ( 2421: – Integer side lengths of a right triangle 2189:If the number has two digits and is of the form 2409: – Algorithms for calculating square roots 2169:represents the preceding digits, its square is 2124:represents the preceding digits, its square is 2552:https://books.google.com/books?id=njEtt7rfexEC 2228:. For example, to calculate the square of 57, 2098:is 1, and the only perfect square of the form 1892:A unique relationship with triangular numbers 130:The usual notation for the square of a number 2937: 2572: 2255:. (The numbers 5, 6, 25, 76, etc. are called 1310:contains no odd powers of primes of the form 904:. Animated 3D visualization on a tetrahedron. 795:. This is also equal to the sum of the first 8: 867:{\displaystyle n^{2}=\sum _{k=1}^{n}(2k-1).} 398: 392: 368: 358: 374:{\displaystyle \lfloor {\sqrt {m}}\rfloor } 4805: 4769: 4733: 4697: 4657: 4331: 4296: 4282: 4171: 3914: 3897: 3812: 3767: 3644: 3602: 3490: 3356: 3347: 3334: 3281: 3238:Possessing a specific set of other numbers 3233: 3167: 3119: 3057: 2961: 2944: 2930: 2922: 2881: 2841: 2729: 2600: 2579: 2565: 2557: 2477:. Cambridge University Press. p. 18. 2353:{\textstyle (25n+x)^{2}-(25n-x)^{2}=100nx} 2202:represents the units digit, its square is 1835:{\displaystyle s=ut+{\tfrac {1}{2}}at^{2}} 1439:is a square number if and only if, in its 2509:On-Line Encyclopedia of Integer Sequences 2433: – Polynomial function of degree two 2396:Some identities involving several squares 2332: 2304: 2283: 2005: 1988: 1975: 1959: 1943: 1933: 1924: 1903: 1897: 1826: 1807: 1790: 1693: 1684: 1665: 1652: 1639: 1626: 1613: 1600: 1590: 1579: 1573: 1535: 1527: 1212: 1199: 1193: 1122: 1055: 1049: 1020: 994: 837: 826: 813: 807: 390: 361: 356: 331: 317: 299: 296: 225: 223: 115:of an integer; in other words, it is the 71:Learn how and when to remove this message 2380: – Number raised to the third power 2186:. For example, the square of 70 is 4900. 1772: 959:th square number, and adding 2, because 437:) smaller than 60 = 3600 are: 34:This article includes a list of general 2450: 2390:Fermat's theorem on sums of two squares 183:. If a square number is represented by 2415: – Two raised to an integer power 1254:{\displaystyle a^{2}-b^{2}=(a+b)(a-b)} 254:A positive integer that has no square 2153:which makes the square equal to 4225. 1522:covers some range of natural numbers 191:; thus, square numbers are a type of 7: 1751:The first values of these sums, the 1494:is the square of 3, so consequently 173:). Hence, a square with side length 1106:{\displaystyle m^{2}-1=(m-1)(m+1).} 381:square numbers up to and including 2457:Some authors also call squares of 1548:{\displaystyle k\geq {\sqrt {m}}.} 218:is again an integer. For example, 40:it lacks sufficient corresponding 14: 2407:Methods of computing square roots 2278:, both ending in 76. In general, 1882:first positive integers; this is 1468:is the square of an integer  985:The square minus one of a number 404:{\displaystyle \lfloor x\rfloor } 16:Product of an integer with itself 4839: 4447:Perfect digit-to-digit invariant 1878:is the square of the sum of the 775: 758: 741: 724: 707: 695: 25: 2372:Brahmagupta–Fibonacci identity 2329: 2313: 2301: 2285: 2086:Every odd perfect square is a 2002: 1989: 1972: 1952: 1940: 1926: 1729: 1714: 1711: 1699: 1296:Lagrange's four-square theorem 1248: 1236: 1233: 1221: 1164:is the only non-zero value of 1097: 1085: 1082: 1070: 858: 843: 244:{\displaystyle {\sqrt {9}}=3,} 1: 3286:Expressible via specific sums 2757:Centered dodecahedral numbers 2550:. Kiran Anil Parulekar, 2012 2156:If the number is of the form 2111:If the number is of the form 1392:divides a square number  1281:. Every odd square is also a 1263:difference-of-squares formula 2762:Centered icosahedral numbers 2742:Centered tetrahedral numbers 2384:Euler's four-square identity 1783:Galileo's law of odd numbers 1557:A square number cannot be a 1142:{\displaystyle 6\times 8=48} 165:is defined as the area of a 4375:Multiplicative digital root 2752:Centered octahedral numbers 2633:Centered heptagonal numbers 2623:Centered pentagonal numbers 2613:Centered triangular numbers 2026:Odd and even square numbers 951:th square, subtracting the 351:Starting with 1, there are 265:For a non-negative integer 87:Square number 16 as sum of 4912: 2857:Squared triangular numbers 2648:Centered decagonal numbers 2643:Centered nonagonal numbers 2638:Centered octagonal numbers 2628:Centered hexagonal numbers 2499:Sloane, N. J. A. 1443:, all exponents are even. 1269:can be easily computed as 876:5 = 25 = 1 + 3 + 5 + 7 + 9 4835: 4818: 4804: 4782: 4768: 4746: 4732: 4710: 4696: 4669: 4656: 4452:Perfect digital invariant 4295: 4281: 4189: 4170: 4027:Superior highly composite 3913: 3896: 3824: 3811: 3779: 3766: 3654: 3643: 3346: 3333: 3291: 3280: 3243: 3232: 3180: 3166: 3129: 3118: 3071: 3056: 2974: 2960: 2088:centered octagonal number 1488:difference of two squares 1318:. This is generalized by 1283:centered octagonal number 989:is always the product of 251:so 9 is a square number. 153:, usually pronounced as " 4896:Squares in number theory 4065:Euler's totient function 3849:Euler–Jacobi pseudoprime 3124:Other polynomial numbers 2823:Square pyramidal numbers 2800:Stella octangula numbers 2437:Square triangular number 1753:square pyramidal numbers 1441:canonical representation 1271:50 − 3 = 2500 − 9 = 2491 3879:Somer–Lucas pseudoprime 3869:Lucas–Carmichael number 3704:Lazy caterer's sequence 2618:Centered square numbers 1568:first square numbers is 785:The expression for the 385:, where the expression 55:more precise citations. 3754:Wedderburn–Etherington 3154:Lucky numbers of Euler 2354: 2038: 2017: 1913: 1836: 1778: 1771: 1745: 1595: 1549: 1279:centered square number 1255: 1157:and itself, and since 1143: 1107: 1038: 1009: 905: 868: 842: 427:The squares (sequence 405: 375: 342: 245: 195:(other examples being 123:and can be written as 92: 4866:Elementary arithmetic 4042:Prime omega functions 3859:Frobenius pseudoprime 3649:Combinatorial numbers 3518:Centered dodecahedral 3311:Primary pseudoperfect 2747:Centered cube numbers 2355: 2033: 2018: 1914: 1912:{\displaystyle T_{n}} 1837: 1776: 1767: 1746: 1575: 1550: 1454:and some number  1256: 1144: 1108: 1039: 1010: 939:. Alternatively, the 885:The sum of the first 884: 869: 822: 406: 376: 343: 246: 210:, square numbers are 144:, but the equivalent 86: 4501:-composition related 4301:Arithmetic functions 3903:Arithmetic functions 3839:Elliptic pseudoprime 3523:Centered icosahedral 3503:Centered tetrahedral 2790:Dodecahedral numbers 2282: 2259:. They are sequence 1923: 1896: 1884:Nicomachus's theorem 1789: 1572: 1526: 1192: 1170:to give a factor of 1153:has factors of only 1121: 1048: 1037:{\displaystyle m+1;} 1019: 993: 895:1 + 3 + 5 + ... + (2 806: 789:th square number is 693:points in a square: 389: 355: 295: 273:th square number is 222: 4427:Kaprekar's constant 3947:Colossally abundant 3834:Catalan pseudoprime 3734:Schröder–Hipparchus 3513:Centered octahedral 3389:Centered heptagonal 3379:Centered pentagonal 3369:Centered triangular 2969:and related numbers 2907:8-hypercube numbers 2902:7-hypercube numbers 2897:6-hypercube numbers 2892:5-hypercube numbers 2862:Tesseractic numbers 2818:Tetrahedral numbers 2795:Icosahedral numbers 2711:Dodecagonal numbers 2534:The Book of Numbers 2401:Integer square root 2257:automorphic numbers 2035:Proof without words 1861:is proportional to 1396:then the square of 1308:prime factorization 1113:For example, since 1008:{\displaystyle m-1} 415:of the number  258:except 1 is called 157:squared". The name 134:is not the product 4845:Mathematics portal 4787:Aronson's sequence 4533:Smarandache–Wellin 4290:-dependent numbers 3997:Primitive abundant 3884:Strong pseudoprime 3874:Perrin pseudoprime 3854:Fermat pseudoprime 3794:Wolstenholme prime 3618:Squared triangular 3404:Centered decagonal 3399:Centered nonagonal 3394:Centered octagonal 3384:Centered hexagonal 2785:Octahedral numbers 2691:Heptagonal numbers 2681:Pentagonal numbers 2671:Triangular numbers 2512:. OEIS Foundation. 2431:Quadratic function 2419:Pythagorean triple 2350: 2151:= 6 × (6 + 1) = 42 2039: 2013: 1909: 1832: 1817: 1779: 1741: 1545: 1379:modular arithmetic 1275:triangular numbers 1251: 1139: 1103: 1034: 1005: 908:There are several 906: 864: 401: 371: 338: 337: 241: 208:real number system 201:triangular numbers 93: 4876:Integer sequences 4853: 4852: 4831: 4830: 4800: 4799: 4764: 4763: 4728: 4727: 4692: 4691: 4652: 4651: 4648: 4647: 4467: 4466: 4277: 4276: 4166: 4165: 4162: 4161: 4108:Aliquot sequences 3919:Divisor functions 3892: 3891: 3864:Lucas pseudoprime 3844:Euler pseudoprime 3829:Carmichael number 3807: 3806: 3762: 3761: 3639: 3638: 3635: 3634: 3631: 3630: 3592: 3591: 3480: 3479: 3437:Square triangular 3329: 3328: 3276: 3275: 3228: 3227: 3162: 3161: 3114: 3113: 3052: 3051: 2919: 2918: 2915: 2914: 2870: 2869: 2852:Pentatope numbers 2831: 2830: 2719: 2718: 2706:Decagonal numbers 2701:Nonagonal numbers 2696:Octagonal numbers 2686:Hexagonal numbers 2546:Kiran Parulekar. 2484:978-0-521-71592-8 2425:Quadratic residue 1816: 1755:, are: (sequence 1736: 1540: 1400:must also divide 1384:In general, if a 783: 782: 366: 325: 307: 230: 81: 80: 73: 4903: 4871:Figurate numbers 4843: 4806: 4775:Natural language 4770: 4734: 4702:Generated via a 4698: 4658: 4563:Digit-reassembly 4528:Self-descriptive 4332: 4297: 4283: 4234:Lucas–Carmichael 4224:Harmonic divisor 4172: 4098:Sparsely totient 4073:Highly cototient 3982:Multiply perfect 3972:Highly composite 3915: 3898: 3813: 3768: 3749:Telephone number 3645: 3603: 3584:Square pyramidal 3566:Stella octangula 3491: 3357: 3348: 3340:Figurate numbers 3335: 3282: 3234: 3168: 3120: 3058: 2962: 2946: 2939: 2932: 2923: 2882: 2842: 2730: 2601: 2588:Figurate numbers 2581: 2574: 2567: 2558: 2514: 2513: 2495: 2489: 2488: 2468: 2462: 2461:perfect squares. 2459:rational numbers 2455: 2359: 2357: 2356: 2351: 2337: 2336: 2309: 2308: 2277: 2273: 2246: 2242: 2238: 2234: 2227: 2217: 2207: 2201: 2195: 2185: 2175: 2168: 2162: 2152: 2145: 2130: 2123: 2117: 2101: 2097: 2093: 2082: 2071: 2051: 2022: 2020: 2019: 2014: 2012: 2011: 2010: 2009: 1980: 1979: 1970: 1969: 1948: 1947: 1938: 1937: 1918: 1916: 1915: 1910: 1908: 1907: 1866: 1860: 1854: 1848: 1841: 1839: 1838: 1833: 1831: 1830: 1818: 1809: 1760: 1750: 1748: 1747: 1742: 1737: 1732: 1694: 1689: 1688: 1670: 1669: 1657: 1656: 1644: 1643: 1631: 1630: 1618: 1617: 1605: 1604: 1594: 1589: 1554: 1552: 1551: 1546: 1541: 1536: 1521: 1517: 1507: 1497: 1493: 1490:.) For example, 1485: 1481: 1471: 1467: 1457: 1453: 1438: 1433: 1429: 1428: 1426: 1425: 1420: 1417: 1408:fails to divide 1407: 1403: 1399: 1395: 1391: 1320:Waring's problem 1317: 1305: 1272: 1268: 1260: 1258: 1257: 1252: 1217: 1216: 1204: 1203: 1181: 1177: 1173: 1169: 1163: 1156: 1148: 1146: 1145: 1140: 1116: 1112: 1110: 1109: 1104: 1060: 1059: 1043: 1041: 1040: 1035: 1014: 1012: 1011: 1006: 988: 980: 973: 958: 950: 942: 938: 915: 903: 889:odd integers is 877: 873: 871: 870: 865: 841: 836: 818: 817: 798: 794: 788: 779: 772: 762: 755: 745: 738: 728: 721: 711: 704: 696: 676: 658: 432: 418: 410: 408: 407: 402: 384: 380: 378: 377: 372: 367: 362: 347: 345: 344: 339: 336: 335: 330: 326: 318: 308: 300: 282: 278: 272: 268: 250: 248: 247: 242: 231: 226: 193:figurate numbers 182: 176: 172: 156: 152: 143: 133: 126: 122: 76: 69: 65: 62: 56: 51:this article by 42:inline citations 29: 28: 21: 4911: 4910: 4906: 4905: 4904: 4902: 4901: 4900: 4856: 4855: 4854: 4849: 4827: 4823:Strobogrammatic 4814: 4796: 4778: 4760: 4742: 4724: 4706: 4688: 4665: 4644: 4628: 4587:Divisor-related 4582: 4542: 4493: 4463: 4400: 4384: 4363: 4330: 4303: 4291: 4273: 4185: 4184:related numbers 4158: 4135: 4102: 4093:Perfect totient 4059: 4036: 3967:Highly abundant 3909: 3888: 3820: 3803: 3775: 3758: 3744:Stirling second 3650: 3627: 3588: 3570: 3527: 3476: 3413: 3374:Centered square 3342: 3325: 3287: 3272: 3239: 3224: 3176: 3175:defined numbers 3158: 3125: 3110: 3081:Double Mersenne 3067: 3048: 2970: 2956: 2954:natural numbers 2950: 2920: 2911: 2866: 2827: 2804: 2766: 2715: 2657: 2590: 2585: 2523: 2521:Further reading 2518: 2517: 2497: 2496: 2492: 2485: 2470: 2469: 2465: 2456: 2452: 2447: 2442: 2367: 2328: 2300: 2280: 2279: 2275: 2271: 2244: 2240: 2236: 2229: 2219: 2209: 2203: 2197: 2190: 2177: 2170: 2164: 2157: 2147: 2132: 2125: 2119: 2112: 2108: 2099: 2095: 2091: 2073: 2057: 2042: 2028: 2001: 1984: 1971: 1955: 1939: 1929: 1921: 1920: 1899: 1894: 1893: 1870:The sum of the 1862: 1856: 1850: 1843: 1822: 1787: 1786: 1756: 1695: 1680: 1661: 1648: 1635: 1622: 1609: 1596: 1570: 1569: 1564:The sum of the 1524: 1523: 1519: 1509: 1499: 1495: 1491: 1483: 1473: 1469: 1459: 1455: 1451: 1436: 1431: 1421: 1418: 1413: 1412: 1410: 1409: 1405: 1401: 1397: 1393: 1389: 1311: 1299: 1270: 1266: 1208: 1195: 1190: 1189: 1185: 1179: 1175: 1171: 1165: 1158: 1154: 1119: 1118: 1114: 1051: 1046: 1045: 1017: 1016: 991: 990: 986: 978: 974:. For example, 960: 952: 944: 940: 917: 913: 894: 875: 809: 804: 803: 796: 790: 786: 767: 750: 733: 716: 699: 683: 660: 645: 642: 608: 574: 540: 506: 472: 428: 425: 416: 411:represents the 387: 386: 382: 353: 352: 313: 312: 293: 292: 280: 274: 270: 266: 220: 219: 178: 174: 170: 154: 148: 135: 131: 124: 120: 77: 66: 60: 57: 47:Please help to 46: 30: 26: 17: 12: 11: 5: 4909: 4907: 4899: 4898: 4893: 4891:Quadrilaterals 4888: 4883: 4878: 4873: 4868: 4858: 4857: 4851: 4850: 4848: 4847: 4836: 4833: 4832: 4829: 4828: 4826: 4825: 4819: 4816: 4815: 4809: 4802: 4801: 4798: 4797: 4795: 4794: 4789: 4783: 4780: 4779: 4773: 4766: 4765: 4762: 4761: 4759: 4758: 4756:Sorting number 4753: 4751:Pancake number 4747: 4744: 4743: 4737: 4730: 4729: 4726: 4725: 4723: 4722: 4717: 4711: 4708: 4707: 4701: 4694: 4693: 4690: 4689: 4687: 4686: 4681: 4676: 4670: 4667: 4666: 4663:Binary numbers 4661: 4654: 4653: 4650: 4649: 4646: 4645: 4643: 4642: 4636: 4634: 4630: 4629: 4627: 4626: 4621: 4616: 4611: 4606: 4601: 4596: 4590: 4588: 4584: 4583: 4581: 4580: 4575: 4570: 4565: 4560: 4554: 4552: 4544: 4543: 4541: 4540: 4535: 4530: 4525: 4520: 4515: 4510: 4504: 4502: 4495: 4494: 4492: 4491: 4490: 4489: 4478: 4476: 4473:P-adic numbers 4469: 4468: 4465: 4464: 4462: 4461: 4460: 4459: 4449: 4444: 4439: 4434: 4429: 4424: 4419: 4414: 4408: 4406: 4402: 4401: 4399: 4398: 4392: 4390: 4389:Coding-related 4386: 4385: 4383: 4382: 4377: 4371: 4369: 4365: 4364: 4362: 4361: 4356: 4351: 4346: 4340: 4338: 4329: 4328: 4327: 4326: 4324:Multiplicative 4321: 4310: 4308: 4293: 4292: 4288:Numeral system 4286: 4279: 4278: 4275: 4274: 4272: 4271: 4266: 4261: 4256: 4251: 4246: 4241: 4236: 4231: 4226: 4221: 4216: 4211: 4206: 4201: 4196: 4190: 4187: 4186: 4175: 4168: 4167: 4164: 4163: 4160: 4159: 4157: 4156: 4151: 4145: 4143: 4137: 4136: 4134: 4133: 4128: 4123: 4118: 4112: 4110: 4104: 4103: 4101: 4100: 4095: 4090: 4085: 4080: 4078:Highly totient 4075: 4069: 4067: 4061: 4060: 4058: 4057: 4052: 4046: 4044: 4038: 4037: 4035: 4034: 4029: 4024: 4019: 4014: 4009: 4004: 3999: 3994: 3989: 3984: 3979: 3974: 3969: 3964: 3959: 3954: 3949: 3944: 3939: 3934: 3932:Almost perfect 3929: 3923: 3921: 3911: 3910: 3901: 3894: 3893: 3890: 3889: 3887: 3886: 3881: 3876: 3871: 3866: 3861: 3856: 3851: 3846: 3841: 3836: 3831: 3825: 3822: 3821: 3816: 3809: 3808: 3805: 3804: 3802: 3801: 3796: 3791: 3786: 3780: 3777: 3776: 3771: 3764: 3763: 3760: 3759: 3757: 3756: 3751: 3746: 3741: 3739:Stirling first 3736: 3731: 3726: 3721: 3716: 3711: 3706: 3701: 3696: 3691: 3686: 3681: 3676: 3671: 3666: 3661: 3655: 3652: 3651: 3648: 3641: 3640: 3637: 3636: 3633: 3632: 3629: 3628: 3626: 3625: 3620: 3615: 3609: 3607: 3600: 3594: 3593: 3590: 3589: 3587: 3586: 3580: 3578: 3572: 3571: 3569: 3568: 3563: 3558: 3553: 3548: 3543: 3537: 3535: 3529: 3528: 3526: 3525: 3520: 3515: 3510: 3505: 3499: 3497: 3488: 3482: 3481: 3478: 3477: 3475: 3474: 3469: 3464: 3459: 3454: 3449: 3444: 3439: 3434: 3429: 3423: 3421: 3415: 3414: 3412: 3411: 3406: 3401: 3396: 3391: 3386: 3381: 3376: 3371: 3365: 3363: 3354: 3344: 3343: 3338: 3331: 3330: 3327: 3326: 3324: 3323: 3318: 3313: 3308: 3303: 3298: 3292: 3289: 3288: 3285: 3278: 3277: 3274: 3273: 3271: 3270: 3265: 3260: 3255: 3250: 3244: 3241: 3240: 3237: 3230: 3229: 3226: 3225: 3223: 3222: 3217: 3212: 3207: 3202: 3197: 3192: 3187: 3181: 3178: 3177: 3171: 3164: 3163: 3160: 3159: 3157: 3156: 3151: 3146: 3141: 3136: 3130: 3127: 3126: 3123: 3116: 3115: 3112: 3111: 3109: 3108: 3103: 3098: 3093: 3088: 3083: 3078: 3072: 3069: 3068: 3061: 3054: 3053: 3050: 3049: 3047: 3046: 3041: 3036: 3031: 3026: 3021: 3016: 3011: 3006: 3001: 2996: 2991: 2986: 2981: 2975: 2972: 2971: 2965: 2958: 2957: 2951: 2949: 2948: 2941: 2934: 2926: 2917: 2916: 2913: 2912: 2910: 2909: 2904: 2899: 2894: 2888: 2886: 2879: 2872: 2871: 2868: 2867: 2865: 2864: 2859: 2854: 2848: 2846: 2839: 2833: 2832: 2829: 2828: 2826: 2825: 2820: 2814: 2812: 2806: 2805: 2803: 2802: 2797: 2792: 2787: 2782: 2776: 2774: 2768: 2767: 2765: 2764: 2759: 2754: 2749: 2744: 2738: 2736: 2727: 2721: 2720: 2717: 2716: 2714: 2713: 2708: 2703: 2698: 2693: 2688: 2683: 2678: 2676:Square numbers 2673: 2667: 2665: 2659: 2658: 2656: 2655: 2650: 2645: 2640: 2635: 2630: 2625: 2620: 2615: 2609: 2607: 2598: 2592: 2591: 2586: 2584: 2583: 2576: 2569: 2561: 2555: 2554: 2544: 2522: 2519: 2516: 2515: 2490: 2483: 2463: 2449: 2448: 2446: 2443: 2441: 2440: 2434: 2428: 2422: 2416: 2410: 2404: 2398: 2393: 2387: 2381: 2375: 2368: 2366: 2363: 2362: 2361: 2349: 2346: 2343: 2340: 2335: 2331: 2327: 2324: 2321: 2318: 2315: 2312: 2307: 2303: 2299: 2296: 2293: 2290: 2287: 2268: 2248: 2187: 2154: 2107: 2104: 2027: 2024: 2008: 2004: 2000: 1997: 1994: 1991: 1987: 1983: 1978: 1974: 1968: 1965: 1962: 1958: 1954: 1951: 1946: 1942: 1936: 1932: 1928: 1906: 1902: 1829: 1825: 1821: 1815: 1812: 1806: 1803: 1800: 1797: 1794: 1740: 1735: 1731: 1728: 1725: 1722: 1719: 1716: 1713: 1710: 1707: 1704: 1701: 1698: 1692: 1687: 1683: 1679: 1676: 1673: 1668: 1664: 1660: 1655: 1651: 1647: 1642: 1638: 1634: 1629: 1625: 1621: 1616: 1612: 1608: 1603: 1599: 1593: 1588: 1585: 1582: 1578: 1559:perfect number 1544: 1539: 1534: 1531: 1375: 1374: 1371: 1368: 1365: 1350: 1349: 1346: 1343: 1340: 1337: 1334: 1250: 1247: 1244: 1241: 1238: 1235: 1232: 1229: 1226: 1223: 1220: 1215: 1211: 1207: 1202: 1198: 1138: 1135: 1132: 1129: 1126: 1102: 1099: 1096: 1093: 1090: 1087: 1084: 1081: 1078: 1075: 1072: 1069: 1066: 1063: 1058: 1054: 1033: 1030: 1027: 1024: 1004: 1001: 998: 983: 982: 863: 860: 857: 854: 851: 848: 845: 840: 835: 832: 829: 825: 821: 816: 812: 781: 780: 773: 764: 763: 756: 747: 746: 739: 730: 729: 722: 713: 712: 705: 682: 679: 641: 640: 637: 634: 631: 628: 625: 622: 619: 616: 613: 609: 607: 606: 603: 600: 597: 594: 591: 588: 585: 582: 579: 575: 573: 572: 569: 566: 563: 560: 557: 554: 551: 548: 545: 541: 539: 538: 535: 532: 529: 526: 523: 520: 517: 514: 511: 507: 505: 504: 501: 498: 495: 492: 489: 486: 483: 480: 477: 473: 471: 470: 467: 464: 461: 458: 455: 452: 449: 446: 443: 439: 424: 421: 400: 397: 394: 370: 365: 360: 334: 329: 324: 321: 316: 311: 306: 303: 240: 237: 234: 229: 146:exponentiation 105:perfect square 79: 78: 33: 31: 24: 15: 13: 10: 9: 6: 4: 3: 2: 4908: 4897: 4894: 4892: 4889: 4887: 4886:Number theory 4884: 4882: 4879: 4877: 4874: 4872: 4869: 4867: 4864: 4863: 4861: 4846: 4842: 4838: 4837: 4834: 4824: 4821: 4820: 4817: 4812: 4807: 4803: 4793: 4790: 4788: 4785: 4784: 4781: 4776: 4771: 4767: 4757: 4754: 4752: 4749: 4748: 4745: 4740: 4735: 4731: 4721: 4718: 4716: 4713: 4712: 4709: 4705: 4699: 4695: 4685: 4682: 4680: 4677: 4675: 4672: 4671: 4668: 4664: 4659: 4655: 4641: 4638: 4637: 4635: 4631: 4625: 4622: 4620: 4617: 4615: 4614:Polydivisible 4612: 4610: 4607: 4605: 4602: 4600: 4597: 4595: 4592: 4591: 4589: 4585: 4579: 4576: 4574: 4571: 4569: 4566: 4564: 4561: 4559: 4556: 4555: 4553: 4550: 4545: 4539: 4536: 4534: 4531: 4529: 4526: 4524: 4521: 4519: 4516: 4514: 4511: 4509: 4506: 4505: 4503: 4500: 4496: 4488: 4485: 4484: 4483: 4480: 4479: 4477: 4474: 4470: 4458: 4455: 4454: 4453: 4450: 4448: 4445: 4443: 4440: 4438: 4435: 4433: 4430: 4428: 4425: 4423: 4420: 4418: 4415: 4413: 4410: 4409: 4407: 4403: 4397: 4394: 4393: 4391: 4387: 4381: 4378: 4376: 4373: 4372: 4370: 4368:Digit product 4366: 4360: 4357: 4355: 4352: 4350: 4347: 4345: 4342: 4341: 4339: 4337: 4333: 4325: 4322: 4320: 4317: 4316: 4315: 4312: 4311: 4309: 4307: 4302: 4298: 4294: 4289: 4284: 4280: 4270: 4267: 4265: 4262: 4260: 4257: 4255: 4252: 4250: 4247: 4245: 4242: 4240: 4237: 4235: 4232: 4230: 4227: 4225: 4222: 4220: 4217: 4215: 4212: 4210: 4207: 4205: 4204:Erdős–Nicolas 4202: 4200: 4197: 4195: 4192: 4191: 4188: 4183: 4179: 4173: 4169: 4155: 4152: 4150: 4147: 4146: 4144: 4142: 4138: 4132: 4129: 4127: 4124: 4122: 4119: 4117: 4114: 4113: 4111: 4109: 4105: 4099: 4096: 4094: 4091: 4089: 4086: 4084: 4081: 4079: 4076: 4074: 4071: 4070: 4068: 4066: 4062: 4056: 4053: 4051: 4048: 4047: 4045: 4043: 4039: 4033: 4030: 4028: 4025: 4023: 4022:Superabundant 4020: 4018: 4015: 4013: 4010: 4008: 4005: 4003: 4000: 3998: 3995: 3993: 3990: 3988: 3985: 3983: 3980: 3978: 3975: 3973: 3970: 3968: 3965: 3963: 3960: 3958: 3955: 3953: 3950: 3948: 3945: 3943: 3940: 3938: 3935: 3933: 3930: 3928: 3925: 3924: 3922: 3920: 3916: 3912: 3908: 3904: 3899: 3895: 3885: 3882: 3880: 3877: 3875: 3872: 3870: 3867: 3865: 3862: 3860: 3857: 3855: 3852: 3850: 3847: 3845: 3842: 3840: 3837: 3835: 3832: 3830: 3827: 3826: 3823: 3819: 3814: 3810: 3800: 3797: 3795: 3792: 3790: 3787: 3785: 3782: 3781: 3778: 3774: 3769: 3765: 3755: 3752: 3750: 3747: 3745: 3742: 3740: 3737: 3735: 3732: 3730: 3727: 3725: 3722: 3720: 3717: 3715: 3712: 3710: 3707: 3705: 3702: 3700: 3697: 3695: 3692: 3690: 3687: 3685: 3682: 3680: 3677: 3675: 3672: 3670: 3667: 3665: 3662: 3660: 3657: 3656: 3653: 3646: 3642: 3624: 3621: 3619: 3616: 3614: 3611: 3610: 3608: 3604: 3601: 3599: 3598:4-dimensional 3595: 3585: 3582: 3581: 3579: 3577: 3573: 3567: 3564: 3562: 3559: 3557: 3554: 3552: 3549: 3547: 3544: 3542: 3539: 3538: 3536: 3534: 3530: 3524: 3521: 3519: 3516: 3514: 3511: 3509: 3508:Centered cube 3506: 3504: 3501: 3500: 3498: 3496: 3492: 3489: 3487: 3486:3-dimensional 3483: 3473: 3470: 3468: 3465: 3463: 3460: 3458: 3455: 3453: 3450: 3448: 3445: 3443: 3440: 3438: 3435: 3433: 3430: 3428: 3425: 3424: 3422: 3420: 3416: 3410: 3407: 3405: 3402: 3400: 3397: 3395: 3392: 3390: 3387: 3385: 3382: 3380: 3377: 3375: 3372: 3370: 3367: 3366: 3364: 3362: 3358: 3355: 3353: 3352:2-dimensional 3349: 3345: 3341: 3336: 3332: 3322: 3319: 3317: 3314: 3312: 3309: 3307: 3304: 3302: 3299: 3297: 3296:Nonhypotenuse 3294: 3293: 3290: 3283: 3279: 3269: 3266: 3264: 3261: 3259: 3256: 3254: 3251: 3249: 3246: 3245: 3242: 3235: 3231: 3221: 3218: 3216: 3213: 3211: 3208: 3206: 3203: 3201: 3198: 3196: 3193: 3191: 3188: 3186: 3183: 3182: 3179: 3174: 3169: 3165: 3155: 3152: 3150: 3147: 3145: 3142: 3140: 3137: 3135: 3132: 3131: 3128: 3121: 3117: 3107: 3104: 3102: 3099: 3097: 3094: 3092: 3089: 3087: 3084: 3082: 3079: 3077: 3074: 3073: 3070: 3065: 3059: 3055: 3045: 3042: 3040: 3037: 3035: 3034:Perfect power 3032: 3030: 3027: 3025: 3024:Seventh power 3022: 3020: 3017: 3015: 3012: 3010: 3007: 3005: 3002: 3000: 2997: 2995: 2992: 2990: 2987: 2985: 2982: 2980: 2977: 2976: 2973: 2968: 2963: 2959: 2955: 2947: 2942: 2940: 2935: 2933: 2928: 2927: 2924: 2908: 2905: 2903: 2900: 2898: 2895: 2893: 2890: 2889: 2887: 2883: 2880: 2878: 2873: 2863: 2860: 2858: 2855: 2853: 2850: 2849: 2847: 2843: 2840: 2838: 2837:4-dimensional 2834: 2824: 2821: 2819: 2816: 2815: 2813: 2811: 2807: 2801: 2798: 2796: 2793: 2791: 2788: 2786: 2783: 2781: 2778: 2777: 2775: 2773: 2769: 2763: 2760: 2758: 2755: 2753: 2750: 2748: 2745: 2743: 2740: 2739: 2737: 2735: 2731: 2728: 2726: 2725:3-dimensional 2722: 2712: 2709: 2707: 2704: 2702: 2699: 2697: 2694: 2692: 2689: 2687: 2684: 2682: 2679: 2677: 2674: 2672: 2669: 2668: 2666: 2664: 2660: 2654: 2651: 2649: 2646: 2644: 2641: 2639: 2636: 2634: 2631: 2629: 2626: 2624: 2621: 2619: 2616: 2614: 2611: 2610: 2608: 2606: 2602: 2599: 2597: 2596:2-dimensional 2593: 2589: 2582: 2577: 2575: 2570: 2568: 2563: 2562: 2559: 2553: 2549: 2545: 2543: 2542:0-387-97993-X 2539: 2535: 2532: 2528: 2527:Conway, J. H. 2525: 2524: 2520: 2511: 2510: 2504: 2500: 2494: 2491: 2486: 2480: 2476: 2475: 2467: 2464: 2460: 2454: 2451: 2444: 2438: 2435: 2432: 2429: 2426: 2423: 2420: 2417: 2414: 2411: 2408: 2405: 2402: 2399: 2397: 2394: 2391: 2388: 2385: 2382: 2379: 2376: 2373: 2370: 2369: 2364: 2347: 2344: 2341: 2338: 2333: 2325: 2322: 2319: 2316: 2310: 2305: 2297: 2294: 2291: 2288: 2269: 2266: 2262: 2258: 2254: 2249: 2232: 2226: 2222: 2216: 2212: 2206: 2200: 2194: 2188: 2184: 2180: 2173: 2167: 2160: 2155: 2150: 2143: 2139: 2135: 2128: 2122: 2115: 2110: 2109: 2106:Special cases 2105: 2103: 2089: 2084: 2080: 2076: 2069: 2065: 2061: 2055: 2050: 2046: 2036: 2032: 2025: 2023: 2006: 1998: 1995: 1992: 1985: 1981: 1976: 1966: 1963: 1960: 1956: 1949: 1944: 1934: 1930: 1904: 1900: 1890: 1887: 1885: 1881: 1877: 1873: 1868: 1865: 1859: 1853: 1849:and constant 1846: 1827: 1823: 1819: 1813: 1810: 1804: 1801: 1798: 1795: 1792: 1784: 1775: 1770: 1766: 1764: 1759: 1754: 1738: 1733: 1726: 1723: 1720: 1717: 1708: 1705: 1702: 1696: 1690: 1685: 1681: 1677: 1674: 1671: 1666: 1662: 1658: 1653: 1649: 1645: 1640: 1636: 1632: 1627: 1623: 1619: 1614: 1610: 1606: 1601: 1597: 1591: 1586: 1583: 1580: 1576: 1567: 1562: 1560: 1555: 1542: 1537: 1532: 1529: 1516: 1512: 1506: 1502: 1489: 1480: 1476: 1466: 1462: 1449: 1448:factorization 1444: 1442: 1424: 1416: 1387: 1382: 1380: 1372: 1369: 1366: 1363: 1362: 1361: 1359: 1355: 1347: 1344: 1341: 1338: 1335: 1332: 1331: 1330: 1328: 1323: 1321: 1315: 1309: 1303: 1297: 1293: 1291: 1286: 1284: 1280: 1276: 1264: 1245: 1242: 1239: 1230: 1227: 1224: 1218: 1213: 1209: 1205: 1200: 1196: 1186: 1183: 1168: 1161: 1152: 1136: 1133: 1130: 1127: 1124: 1100: 1094: 1091: 1088: 1079: 1076: 1073: 1067: 1064: 1061: 1056: 1052: 1031: 1028: 1025: 1022: 1002: 999: 996: 977: 976: 975: 971: 967: 963: 956: 948: 936: 932: 928: 924: 920: 911: 902: 898: 892: 888: 883: 879: 874:For example, 861: 855: 852: 849: 846: 838: 833: 830: 827: 823: 819: 814: 810: 801: 793: 778: 774: 770: 766: 765: 761: 757: 753: 749: 748: 744: 740: 736: 732: 731: 727: 723: 719: 715: 714: 710: 706: 702: 698: 697: 694: 692: 688: 680: 678: 675: 671: 667: 663: 656: 652: 648: 638: 635: 632: 629: 626: 623: 620: 617: 614: 611: 610: 604: 601: 598: 595: 592: 589: 586: 583: 580: 577: 576: 570: 567: 564: 561: 558: 555: 552: 549: 546: 543: 542: 536: 533: 530: 527: 524: 521: 518: 515: 512: 509: 508: 502: 499: 496: 493: 490: 487: 484: 481: 478: 475: 474: 468: 465: 462: 459: 456: 453: 450: 447: 444: 441: 440: 438: 436: 431: 422: 420: 414: 395: 363: 349: 332: 327: 322: 319: 314: 309: 304: 301: 290: 286: 277: 263: 261: 257: 252: 238: 235: 232: 227: 217: 213: 209: 204: 202: 198: 194: 190: 186: 181: 168: 164: 160: 151: 147: 142: 138: 128: 118: 114: 110: 106: 102: 101:square number 98: 90: 85: 75: 72: 64: 61:February 2012 54: 50: 44: 43: 37: 32: 23: 22: 19: 4578:Transposable 4442:Narcissistic 4349:Digital root 4269:Super-Poulet 4229:Jordan–Pólya 4178:prime factor 4083:Noncototient 4050:Almost prime 4032:Superperfect 4007:Refactorable 4002:Quasiperfect 3977:Hyperperfect 3818:Pseudoprimes 3789:Wall–Sun–Sun 3724:Ordered Bell 3694:Fuss–Catalan 3606:non-centered 3556:Dodecahedral 3533:non-centered 3431: 3419:non-centered 3321:Wolstenholme 3066:× 2 ± 1 3063: 3062:Of the form 3029:Eighth power 3009:Fourth power 2998: 2885:non-centered 2845:non-centered 2780:Cube numbers 2772:non-centered 2675: 2663:non-centered 2653:Star numbers 2547: 2533: 2506: 2493: 2473: 2466: 2453: 2413:Power of two 2378:Cubic number 2252: 2230: 2224: 2220: 2214: 2210: 2204: 2198: 2192: 2182: 2178: 2171: 2165: 2158: 2148: 2141: 2137: 2133: 2126: 2120: 2113: 2085: 2078: 2074: 2067: 2063: 2059: 2048: 2044: 2040: 1891: 1888: 1879: 1871: 1869: 1863: 1857: 1851: 1844: 1780: 1768: 1565: 1563: 1556: 1514: 1510: 1504: 1500: 1478: 1474: 1464: 1460: 1445: 1422: 1414: 1383: 1376: 1358:prime number 1351: 1324: 1313: 1301: 1294: 1287: 1261:This is the 1187: 1184: 1166: 1159: 1151:prime number 984: 969: 965: 961: 954: 946: 934: 930: 929:− 1) + n = ( 926: 922: 918: 907: 900: 896: 890: 886: 791: 784: 768: 751: 734: 717: 700: 690: 686: 684: 673: 669: 665: 661: 654: 650: 646: 643: 426: 350: 275: 264: 253: 212:non-negative 205: 197:cube numbers 188: 184: 179: 158: 149: 140: 136: 129: 111:that is the 104: 100: 94: 67: 58: 39: 18: 4599:Extravagant 4594:Equidigital 4549:permutation 4508:Palindromic 4482:Automorphic 4380:Sum-product 4359:Sum-product 4314:Persistence 4209:Erdős–Woods 4131:Untouchable 4012:Semiperfect 3962:Hemiperfect 3623:Tesseractic 3561:Icosahedral 3541:Tetrahedral 3472:Dodecagonal 3173:Recursively 3044:Prime power 3019:Sixth power 3014:Fifth power 2994:Power of 10 2952:Classes of 2877:dimensional 2237:25 + 7 = 32 1290:even number 800:odd numbers 685:The number 260:square-free 216:square root 167:unit square 97:mathematics 53:introducing 4860:Categories 4811:Graphemics 4684:Pernicious 4538:Undulating 4513:Pandigital 4487:Trimorphic 4088:Nontotient 3937:Arithmetic 3551:Octahedral 3452:Heptagonal 3442:Pentagonal 3427:Triangular 3268:Sierpiński 3190:Jacobsthal 2989:Power of 3 2984:Power of 2 2531:Guy, R. K. 1492:100 − 9991 1149:. Since a 1117:, one has 681:Properties 283:being the 36:references 4568:Parasitic 4417:Factorion 4344:Digit sum 4336:Digit sum 4154:Fortunate 4141:Primorial 4055:Semiprime 3992:Practical 3957:Descartes 3952:Deficient 3942:Betrothed 3784:Wieferich 3613:Pentatope 3576:pyramidal 3467:Decagonal 3462:Nonagonal 3457:Octagonal 3447:Hexagonal 3306:Practical 3253:Congruent 3185:Fibonacci 3149:Loeschian 2810:pyramidal 2323:− 2311:− 2245:57 = 3249 2056:8, since 1675:⋯ 1577:∑ 1533:≥ 1243:− 1206:− 1180:3 = 2 − 1 1128:× 1077:− 1062:− 1000:− 933:− 1) + (2 910:recursive 853:− 824:∑ 639:59 = 3481 636:58 = 3364 633:57 = 3249 630:56 = 3136 627:55 = 3025 624:54 = 2916 621:53 = 2809 618:52 = 2704 615:51 = 2601 612:50 = 2500 605:49 = 2401 602:48 = 2304 599:47 = 2209 596:46 = 2116 593:45 = 2025 590:44 = 1936 587:43 = 1849 584:42 = 1764 581:41 = 1681 578:40 = 1600 571:39 = 1521 568:38 = 1444 565:37 = 1369 562:36 = 1296 559:35 = 1225 556:34 = 1156 553:33 = 1089 550:32 = 1024 399:⌋ 393:⌊ 369:⌋ 359:⌊ 177:has area 4881:Integers 4640:Friedman 4573:Primeval 4518:Repdigit 4475:-related 4422:Kaprekar 4396:Meertens 4319:Additive 4306:dynamics 4214:Friendly 4126:Sociable 4116:Amicable 3927:Abundant 3907:dynamics 3729:Schröder 3719:Narayana 3689:Eulerian 3679:Delannoy 3674:Dedekind 3495:centered 3361:centered 3248:Amenable 3205:Narayana 3195:Leonardo 3091:Mersenne 3039:Powerful 2979:Achilles 2734:centered 2605:centered 2365:See also 2276:26 = 676 2272:24 = 576 2070:+ 1) + 1 2062:+ 1) = 4 1482:divides 1044:that is, 972:− 2) + 2 968:− 1) − ( 925:− 1) + ( 771:= 5 = 25 754:= 4 = 16 668:− 1) + ( 653:− 1) = 2 547:31 = 961 544:30 = 900 537:29 = 841 534:28 = 784 531:27 = 729 528:26 = 676 525:25 = 625 522:24 = 576 519:23 = 529 516:22 = 484 513:21 = 441 510:20 = 400 503:19 = 361 500:18 = 324 497:17 = 289 494:16 = 256 491:15 = 225 488:14 = 196 485:13 = 169 482:12 = 144 479:11 = 121 476:10 = 100 423:Examples 289:rational 256:divisors 4813:related 4777:related 4741:related 4739:Sorting 4624:Vampire 4609:Harshad 4551:related 4523:Repunit 4437:Lychrel 4412:Dudeney 4264:Størmer 4259:Sphenic 4244:Regular 4182:divisor 4121:Perfect 4017:Sublime 3987:Perfect 3714:Motzkin 3669:Catalan 3210:Padovan 3144:Leyland 3139:Idoneal 3134:Hilbert 3106:Woodall 2875:Higher 2501:(ed.). 2263:in the 2261:A003226 2213:= 25 + 1761:in the 1758:A000330 1496:100 − 3 1430:, then 1427:⁠ 1411:⁠ 1354:base 12 1327:base 10 1267:47 × 53 899:− 1) = 737:= 3 = 9 720:= 2 = 4 703:= 1 = 1 672:− 1) + 433:in the 430:A000290 279:, with 206:In the 117:product 109:integer 89:gnomons 49:improve 4679:Odious 4604:Frugal 4558:Cyclic 4547:Digit- 4254:Smooth 4239:Pronic 4199:Cyclic 4176:Other 4149:Euclid 3799:Wilson 3773:Primes 3432:Square 3301:Polite 3263:Riesel 3258:Knödel 3220:Perrin 3101:Thabit 3086:Fermat 3076:Cullen 2999:Square 2967:Powers 2540:  2481:  2241:7 = 49 2208:where 2196:where 2176:where 2163:where 2131:where 2118:where 2102:is 9. 2072:, and 2054:modulo 1874:first 1842:, for 1518:where 1388:  1115:7 = 49 469:9 = 81 466:8 = 64 463:7 = 49 460:6 = 36 457:5 = 25 454:4 = 16 285:zeroth 269:, the 159:square 113:square 107:is an 38:, but 4720:Prime 4715:Lucky 4704:sieve 4633:Other 4619:Smith 4499:Digit 4457:Happy 4432:Keith 4405:Other 4249:Rough 4219:Giuga 3684:Euler 3546:Cubic 3200:Lucas 3096:Proth 2445:Notes 2243:, so 2100:2 + 1 2096:2 − 1 2047:) = 4 1876:cubes 1472:then 1458:, if 1404:; if 1386:prime 451:3 = 9 448:2 = 4 445:1 = 1 442:0 = 0 413:floor 281:0 = 0 171:1 × 1 125:3 × 3 4674:Evil 4354:Self 4304:and 4194:Blum 3905:and 3709:Lobb 3664:Cake 3659:Bell 3409:Star 3316:Ulam 3215:Pell 3004:Cube 2538:ISBN 2529:and 2507:The 2479:ISBN 2274:and 2265:OEIS 2239:and 2235:and 2218:and 2205:aabb 2144:+ 1) 2081:+ 1) 1763:OEIS 1304:+ 7) 1015:and 964:= 2( 957:− 2) 949:− 1) 937:− 1) 435:OEIS 199:and 163:area 99:, a 4792:Ban 4180:or 3699:Lah 2342:100 2253:376 2233:= 7 1919:is: 1847:= 0 1508:to 1352:In 1325:In 1316:+ 3 1300:4(8 1182:). 1162:= 2 921:= ( 664:= ( 657:− 1 649:− ( 203:). 103:or 95:In 4862:: 2505:. 2317:25 2289:25 2267:.) 2223:= 2221:bb 2211:aa 2181:= 2174:00 2136:= 2129:25 2058:(2 2043:(2 1886:. 1765:) 1561:. 1513:+ 1503:− 1477:− 1463:− 1381:. 1322:. 1285:. 1137:48 893:. 878:. 677:. 419:. 348:. 262:. 139:× 127:. 3064:a 2945:e 2938:t 2931:v 2580:e 2573:t 2566:v 2487:. 2348:x 2345:n 2339:= 2334:2 2330:) 2326:x 2320:n 2314:( 2306:2 2302:) 2298:x 2295:+ 2292:n 2286:( 2247:. 2231:m 2225:m 2215:m 2199:m 2193:m 2191:5 2183:m 2179:n 2172:n 2166:m 2161:0 2159:m 2149:n 2142:m 2140:( 2138:m 2134:n 2127:n 2121:m 2116:5 2114:m 2092:2 2079:n 2077:( 2075:n 2068:n 2066:( 2064:n 2060:n 2049:n 2045:n 2007:2 2003:) 1999:1 1996:+ 1993:n 1990:( 1986:T 1982:= 1977:2 1973:) 1967:1 1964:+ 1961:n 1957:T 1953:( 1950:+ 1945:2 1941:) 1935:n 1931:T 1927:( 1905:n 1901:T 1880:n 1872:n 1864:t 1858:s 1852:a 1845:u 1828:2 1824:t 1820:a 1814:2 1811:1 1805:+ 1802:t 1799:u 1796:= 1793:s 1739:. 1734:6 1730:) 1727:1 1724:+ 1721:N 1718:2 1715:( 1712:) 1709:1 1706:+ 1703:N 1700:( 1697:N 1691:= 1686:2 1682:N 1678:+ 1672:+ 1667:2 1663:4 1659:+ 1654:2 1650:3 1646:+ 1641:2 1637:2 1633:+ 1628:2 1624:1 1620:+ 1615:2 1611:0 1607:= 1602:2 1598:n 1592:N 1587:0 1584:= 1581:n 1566:n 1543:. 1538:m 1530:k 1520:k 1515:n 1511:k 1505:n 1501:k 1484:m 1479:n 1475:k 1470:n 1465:m 1461:k 1456:k 1452:m 1437:m 1432:m 1423:p 1419:/ 1415:m 1406:p 1402:m 1398:p 1394:m 1390:p 1314:k 1312:4 1302:m 1249:) 1246:b 1240:a 1237:( 1234:) 1231:b 1228:+ 1225:a 1222:( 1219:= 1214:2 1210:b 1201:2 1197:a 1176:3 1172:1 1167:m 1160:m 1155:1 1134:= 1131:8 1125:6 1101:. 1098:) 1095:1 1092:+ 1089:m 1086:( 1083:) 1080:1 1074:m 1071:( 1068:= 1065:1 1057:2 1053:m 1032:; 1029:1 1026:+ 1023:m 1003:1 997:m 987:m 981:. 970:n 966:n 962:n 955:n 953:( 947:n 945:( 941:n 935:n 931:n 927:n 923:n 919:n 914:n 901:n 897:n 891:n 887:n 862:. 859:) 856:1 850:k 847:2 844:( 839:n 834:1 831:= 828:k 820:= 815:2 811:n 797:n 792:n 787:n 769:m 752:m 735:m 718:m 701:m 691:m 687:m 674:n 670:n 666:n 662:n 655:n 651:n 647:n 417:x 396:x 383:m 364:m 333:2 328:) 323:3 320:2 315:( 310:= 305:9 302:4 276:n 271:n 267:n 239:, 236:3 233:= 228:9 189:n 185:n 180:n 175:n 169:( 155:n 150:n 141:n 137:n 132:n 121:3 91:. 74:) 68:( 63:) 59:( 45:.

Index

references
inline citations
improve
introducing
Learn how and when to remove this message

gnomons
mathematics
integer
square
product
exponentiation
area
unit square
figurate numbers
cube numbers
triangular numbers
real number system
non-negative
square root
divisors
square-free
zeroth
rational
floor
A000290
OEIS


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