A097958 Primes p such that p divides 6^((p-1)/2) - 3^((p-1)/2).

3, 7, 17, 23, 31, 41, 47, 71, 73, 79, 89, 97, 103, 113, 127, 137, 151, 167, 191, 193, 199, 223, 233, 239, 241, 257, 263, 271, 281, 311, 313, 337, 353, 359, 367, 383, 401, 409, 431, 433, 439, 449, 457, 463, 479, 487, 503, 521, 569, 577, 593, 599, 601, 607, 617

Offset: 1

Author

Cino Hilliard, Sep 06 2004

Keywords

• nonn
• easy

Comments

Apart from the first term, the same as A001132 or A038873. - Jianing Song, Apr 21 2022

Links

• Jianing Song, Table of n, a(n) for n = 1..10000 (terms 1..998 from Harvey P. Dale)

Crossrefs

Cf. A001132, A038873.

Programs

Mathematica

Select[Prime[Range[150]],Divisible[6^((#-1)/2)-3^((#-1)/2),#]&] (* Harvey P. Dale, Dec 25 2021 *)

PARI

\s = +-1,d=diff ptopm1d2(n,x,d,s) = { forprime(p=3,n,p2=(p-1)/2; y=x^p2 + s*(x-d)^p2; if(y%p==0,print1(p","))) }

PARI

isA097958(p) = (p==3) || (isprime(p) && kronecker(p,2)==1) \\ Jianing Song, Apr 21 2022

Formula

Equals {3} union A001132. - Jianing Song, Apr 21 2022

Extensions

Definition corrected by Cino Hilliard, Nov 10 2008

Definition clarified by Harvey P. Dale, Dec 25 2021

Offset corrected by Jianing Song, Apr 21 2022