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.

Previous Showing 31-33 of 33 results.

A085321 First difference sequence of A003337, i.e., consecutive differences between those consecutive numbers which are sums of three 4th powers.

Original entry on oeis.org

15, 15, 15, 35, 15, 15, 50, 15, 65, 15, 15, 15, 50, 15, 65, 95, 15, 65, 34, 15, 15, 50, 15, 46, 19, 95, 15, 65, 175, 114, 15, 32, 15, 15, 3, 47, 15, 65, 48, 47, 15, 65, 175, 67, 47, 15, 65, 175, 226, 15, 15, 50, 15, 48, 17, 30, 15, 50, 15, 65, 110, 65, 114, 15, 65, 110, 65
Offset: 1

Views

Author

Labos Elemer, Jul 01 2003

Keywords

Examples

			48 = 16 + 16 + 16, 83 = 81 + 1 + 1, 81 - 48 = 35 = a(4);
Certain differences occur consequently like 15, 30, 31, 32, 49, 50, 64, 65, 175, etc.;
Distance of closest neighbors equals 1,
like those of 7202 = 6561 + 625 + 16 and 7203 = 2401 + 2401 + 2401.

Crossrefs

Cf. A003337, A003327-A003399.

Programs

  • Mathematica
    {m=12, k=5, m^k}; t=Union[Flatten[Table[Table[Table[Table[w^k+q^k+t^k+u^k, {w, 1, m}], {q, 1, m}], {t, 1, m}], {u, 1, m}]]]; Length[t]; dt=Delete[ -RotateRight[t]+t, 1]; Sort[dt]

A085322 Terms m of A003337 such that m+1 is also in A003337. I.e., smaller one of two consecutive numbers, both equal to a sum of three 4th powers.

Original entry on oeis.org

4802, 7202, 10257, 14802, 15522, 38577, 45602, 57122, 57202, 76832, 86002, 90337, 94817, 109777, 112162, 116177, 131697, 135712, 136897, 155617, 163697, 171137, 188577, 243777, 260642, 284562, 296882, 332417, 388962, 390962, 391922, 459457, 474402, 617057, 637712
Offset: 1

Views

Author

Labos Elemer, Jul 01 2003

Keywords

Examples

			Distance of closest neighbors in A003337 equals 1: 7202 = 6561 + 625 + 16 and 7203 = 2401 + 2401 + 2401 are corresponding neighbors, so 7202 is a term.

Links

Crossrefs

Cf. A003337, A003327-A003399, A085321.

Programs

  • Mathematica
    {m=25, k=4, m^k} t=Union[Flatten[Table[Table[Table[w^k+q^k+t^k, {w, 1, m}], {q, 1, m}], {t, 1, m}]]] dt=Delete[ -RotateRight[t]+t, 1]; Part[t, Flatten[Position[dt, 1]]]
Select[Partition[Union[Total/@Tuples[Range[25]^4,3]],2,1],#[[2]]-#[[1]] == 1&][[All,1]] (* Harvey P. Dale, Jul 31 2020 *)

Extensions

More terms from Amiram Eldar, Mar 08 2025

A085320 First difference sequence of A003349, i.e., consecutive differences between those consecutive numbers which are sums of four 5th powers.

Original entry on oeis.org

31, 31, 31, 31, 118, 31, 31, 31, 149, 31, 31, 180, 31, 211, 55, 31, 31, 31, 149, 31, 31, 180, 31, 211, 297, 31, 31, 180, 31, 211, 539, 31, 24, 31, 31, 31, 94, 55, 31, 31, 180, 31, 211, 242, 55, 31, 31, 180, 31, 211, 539, 31, 211, 781, 55, 31, 31, 180, 31, 211, 539, 31
Offset: 1

Views

Author

Labos Elemer, Jul 01 2003

Keywords

Examples

			35 = 1 + 1 + 1 + 32, 66 = 32 + 32 + 1 + 1, a(1) = 66 - 33 = 31.
Certain differences occur rather consequently like 31, 55, 113, 180, 207, 211, 539, etc.;
Distance of closest observed neighbors equals 2 like those of 33858 and 33856.

Crossrefs

Cf. A003349, A003327-A003399.

Programs

  • Mathematica
    {m=12, k=5, m^k}; t=Union[Flatten[Table[Table[Table[Table[w^k+q^k+t^k+u^k, {w, 1, m}], {q, 1, m}], {t, 1, m}], {u, 1, m}]]]; Length[t]; dt=Delete[ -RotateRight[t]+t, 1]; Sort[dt]
Previous Showing 31-33 of 33 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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