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.

A331427 Prime numbers p such that p^2 divides 41^(p-1) - 1.

Original entry on oeis.org

2, 29, 1025273, 138200401
Offset: 1

Views

Author

Seiichi Manyama, Jan 16 2020

Keywords

References

  • Paulo Ribenboim, The Little Book of Bigger Primes, Springer-Verlag NY 2004. See p. 233.

Crossrefs

Wieferich primes to base b: A001220 (b=2), A014127 (b=3), A123692 (b=5), A123693 (b=7), A128667 (b=13), A128668 (b=17), A090968 (b=19), A128669 (b=23), A331424 (b=31), A331426 (b=37), this sequence (b=41).
Cf. A039951.

Programs

  • Mathematica
    Select[Range[1.1*10^6], PrimeQ[#] && PowerMod[41, # - 1, #^2] == 1 &] (* Amiram Eldar, May 05 2021 *)
  • PARI
    forprime(p=2, 1e8, if(Mod(41, p^2)^(p-1)==1, print1(p", ")))