cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-10 of 14 results. Next

A260046 Composites whose prime factorization in base 2 is an anagram of the number in base 2.

Original entry on oeis.org

25, 159, 175, 242, 245, 287, 303, 319, 459, 500, 575, 591, 623, 679, 687, 699, 735, 763, 1135, 1167, 1203, 1243, 1247, 1271, 1351, 1371, 1391, 1525, 1631, 1734, 1911, 2167, 2173, 2231, 2285, 2295, 2319, 2359, 2463, 2471, 2495, 2519, 2743, 2779, 2787, 2863, 2890
Offset: 1

Views

Author

Stephen Tucker, Jul 14 2015

Keywords

Examples

			25 = 5^2. In base 2, 11001 = 101^10.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[10^6], !PrimeQ[#] && Sort@ IntegerDigits[#, 2] == Sort@ Flatten@ IntegerDigits[ Select[ Flatten@ FactorInteger@ #, #>1 &], 2] &] (* Giovanni Resta, Jul 14 2015 *)

A260047 Composites whose prime factorization in base 3 is an anagram of the number in base 3.

Original entry on oeis.org

16, 25, 160, 960, 1125, 1888, 3146, 3488, 3549, 4064, 4235, 4335, 4928, 5415, 5746, 5875, 7502, 7847, 8224, 8414, 8954, 9633, 10016, 10192, 11840, 12103, 12256, 12704, 12716, 12844, 16415, 16820, 16954, 18784, 18880, 19264, 19355, 19481, 22838
Offset: 1

Views

Author

Stephen Tucker, Jul 14 2015

Keywords

Examples

			16 = 2^4. In base 3, 121 = 2^11.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[10^6], !PrimeQ[#] && Sort@ IntegerDigits[#, 3] == Sort@ Flatten@ IntegerDigits[ Select[ Flatten@ FactorInteger@ #, #>1 &], 3] &] (* Giovanni Resta, Jul 14 2015 *)

A260048 Composites whose prime factorization in base 4 is an anagram of the number in base 4.

Original entry on oeis.org

25, 637, 722, 1135, 1243, 1519, 1639, 1734, 1863, 2167, 4735, 4855, 4939, 5311, 5746, 5886, 5967, 6381, 6589, 6713, 7003, 7339, 7407, 7774, 8154, 8503, 8667, 8703, 9457, 11123, 11221, 11711, 15471, 16735, 17779, 17965, 18079, 18283, 18477, 18589
Offset: 1

Views

Author

Stephen Tucker, Jul 14 2015

Keywords

Examples

			25 = 5^2. In base 4, 121 = 11^2.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[10^6], !PrimeQ[#] && Sort@ IntegerDigits[#, 4] == Sort@ Flatten@ IntegerDigits[ Select[ Flatten@ FactorInteger@ #, #>1 &], 4] &] (* Giovanni Resta, Jul 14 2015 *)

A260049 Composites whose prime factorization in base 5 is an anagram of the number in base 5.

Original entry on oeis.org

2312, 2432, 3232, 5319, 5373, 10112, 10719, 11691, 14592, 15417, 19712, 20412, 21688, 22194, 23841, 24705, 25920, 26217, 32724, 36096, 39168, 41823, 42194, 42417, 43713, 51597, 58029, 59211, 61557, 62192, 66944, 67068, 68553, 72873, 76464
Offset: 1

Views

Author

Stephen Tucker, Jul 14 2015

Keywords

Examples

			2312 = 2^3 * 17^2. In base 5, 33222 = 2^3 * 32^2.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[10^5], !PrimeQ[#] && Sort@ IntegerDigits[#, 5] == Sort@ Flatten@ IntegerDigits[ Select[ Flatten@ FactorInteger@ #, #>1 &], 5] &] (* Giovanni Resta, Jul 14 2015 *)

A260050 Composites whose prime factorization in base 6 is an anagram of the number in base 6.

Original entry on oeis.org

16, 32, 49, 57, 314, 327, 377, 417, 575, 837, 1387, 1417, 1647, 1754, 1874, 1934, 1977, 2157, 2355, 2474, 2487, 2517, 2577, 2987, 3757, 5157, 5597, 7424, 8227, 9050, 9824, 10394, 10474, 10784, 10834, 11014, 11229, 11654, 11667, 12317, 12741, 13067
Offset: 1

Views

Author

Stephen Tucker, Jul 14 2015

Keywords

Examples

			16 = 2^4. In base 6, 24 = 2^4.
		

Crossrefs

A260051 Composites whose prime factorization in base 7 is an anagram of the number in base 7.

Original entry on oeis.org

7136, 9056, 30057, 32076, 40256, 40678, 46400, 71125, 90334, 145152, 150027, 159975, 166281, 177315, 193227, 201057, 207681, 207843, 212000, 218080, 224192, 225195, 229407, 246777, 263031, 265184, 297027, 298144, 298208, 306624, 318096
Offset: 1

Views

Author

Stephen Tucker, Jul 14 2015

Keywords

Examples

			7136 = 2^5 * 223. In base 7, 26543 = 2^5 * 436.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[10^5], !PrimeQ[#] && Sort@ IntegerDigits[#, 7] == Sort@ Flatten@ IntegerDigits[ Select[ Flatten@ FactorInteger@ #, #>1 &], 7] &] (* Giovanni Resta, Jul 14 2015 *)

A260052 Composites whose prime factorization in base 8 is an anagram of the number in base 8.

Original entry on oeis.org

27, 85, 169, 175, 771, 4369, 4803, 5359, 6805, 7339, 19405, 21689, 24433, 36526, 40405, 40799, 41723, 41773, 43999, 44353, 46131, 47447, 48819, 49917, 54965, 71047, 74273, 87823, 107892, 130683, 131026, 139157, 246977, 268885, 269977
Offset: 1

Views

Author

Stephen Tucker, Jul 14 2015

Keywords

Examples

			27 = 3^3. In base 8, 33 = 3^3.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[10^6], !PrimeQ[#] && Sort@ IntegerDigits[#, 8] == Sort@ Flatten@ IntegerDigits[ Select[ Flatten@ FactorInteger@ #, #>1 &], 8] &] (* Giovanni Resta, Jul 14 2015 *)

A260053 Composites whose prime factorization in base 9 is an anagram of the number in base 9.

Original entry on oeis.org

72646, 74176, 75295, 78475, 134832, 189771, 255619, 422233, 440561, 586022, 638582, 644799, 655312, 659712, 701078, 855296, 882278, 919488, 1197500, 1213750, 1328102, 1329280, 1428352, 1451968, 1581088, 1585184, 1718857
Offset: 1

Views

Author

Stephen Tucker, Jul 14 2015

Keywords

Examples

			72646 = 2 * 7 * 5189. In base 9, 120577 = 2 * 7 * 7105.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[10^6], !PrimeQ[#] && Sort@ IntegerDigits[#, 9] == Sort@ Flatten@ IntegerDigits[ Select[ Flatten@ FactorInteger@ #, #>1 &], 9] &] (* Giovanni Resta, Jul 14 2015 *)

A260054 Composites whose prime factorization in base 11 is an anagram of the number in base 11.

Original entry on oeis.org

4617, 7047, 18193, 33534, 180803, 196352, 217147, 283983, 386391, 422144, 448147, 616977, 705875, 842967, 886250, 926336, 947125, 954747, 1169536, 1235875, 1373375, 1866955, 1883049, 1968259
Offset: 1

Views

Author

Stephen Tucker, Jul 14 2015

Keywords

Examples

			4617 = 3^5 * 19. In base 11, 3518 = 3^5 * 18.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[10^6], !PrimeQ[#] && Sort@ IntegerDigits[#, 11] == Sort@ Flatten@ IntegerDigits[ Select[ Flatten@ FactorInteger@ #, #>1 &], 11] &] (* Giovanni Resta, Jul 14 2015 *)

A260055 Composites whose prime factorization in base 12 is an anagram of the number in base 12.

Original entry on oeis.org

169, 185, 219, 2165, 2402, 3981, 4205, 10031, 21349, 21907, 22049, 24199, 26919, 27746, 28802, 29767, 29919, 31107, 46749, 71375, 251521, 252257, 252361, 259565, 275237, 280587, 292159, 293011, 301163, 303161, 305765
Offset: 1

Views

Author

Stephen Tucker, Jul 14 2015

Keywords

Examples

			169 = 13^2. In base 12, 121 = 11^2.
		

Crossrefs

Programs

  • PARI
    isok(n, b) = {f = factor(n); v = []; for (i=1, #f~, v = concat(v, digits(f[i,1], b)); if (f[i,2]!= 1, v = concat(v, digits(f[i,2], b)));); vecsort(v) == vecsort(digits(n, b));}
    lista(nn, b=12) = forcomposite(n=1, nn, if (isok(n,b), print1(n, ", "))); \\ Michel Marcus, Jul 14 2015
Showing 1-10 of 14 results. Next