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 1-3 of 3 results.

A276671 Positive integers k such that 3^k == 2 (mod k).

Original entry on oeis.org

1, 2929, 9742277641, 23341869101, 15092205901438895, 16311037042239935
Offset: 1

Views

Author

Max Alekseyev, Oct 05 2016

Keywords

Comments

No other terms below 2*10^16. A larger term: 31744873758348589012852097851.

Crossrefs

Cf. A015973, A067945, A015949, A055686, A242865, A234535, A234536, A050259.

Programs

  • Mathematica
    Join[{1}, Select[Range[10000], PowerMod[3, #, #] == 2 &]] (* Alonso del Arte, Oct 11 2016 *)
  • PARI
    isok(n) = Mod(3, n)^n == Mod(2, n); \\ Dmitry Ezhov, Sep 28 2016

Extensions

Order of terms corrected by Felix Fröhlich, Oct 06 2016
a(5)-a(6) from Sergey Paramonov, Oct 03 2021

A055688 Numbers k such that 5^k == -1 (mod k-1).

Original entry on oeis.org

2, 3, 7, 14, 15, 175, 855, 2695, 78127, 103974, 106695, 121975, 420210, 487375, 1299375, 2174655, 3895095, 4151455, 5842215, 5951130, 6508335, 10637055, 20117895, 24482958, 31999695, 32282054, 32620203, 32872455, 34258455
Offset: 1

Views

Author

Robert G. Wilson v, Jun 09 2000

Keywords

Links

Crossrefs

Cf. A055685, A055686, A055687, A055689, A055690, A055691, A055692, A055693, A055694, A055695.

Programs

  • Mathematica
    Do[If[PowerMod[5, n, n-1]==n-2, Print[n]], {n, 2, 10^8}]
Select[Range[2,35*10^6],PowerMod[5,#,#-1]==#-2&] (* Harvey P. Dale, Aug 13 2024 *)

Extensions

a(22) corrected by Amiram Eldar, Jul 23 2021

A055690 Numbers k such that 7^k == -1 (mod k-1).

Original entry on oeis.org

2, 3, 5, 6, 9, 26, 45, 66, 87, 345, 765, 906, 3926, 8405, 11766, 23805, 35145, 42966, 59685, 95289, 317250, 413325, 416757, 722745, 770066, 890825, 938457, 1325826, 1921986, 3315378, 3675555, 5299250, 6791445, 6899685, 9371826, 10892313
Offset: 1

Views

Author

Robert G. Wilson v, Jun 09 2000

Keywords

Links

Crossrefs

Cf. A055685, A055686, A055687, A055688, A055689, A055691, A055692, A055693, A055694, A055695.

Programs

  • Mathematica
    Do[If[PowerMod[7, n, n-1]==n-2, Print[n]], {n, 2, 2*10^7}]
Showing 1-3 of 3 results.

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

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