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A097958
Primes p such that p divides 6^((p-1)/2) - 3^((p-1)/2).
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
1,1
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)
FORMULA
Equals {3} union A001132. - Jianing Song, Apr 21 2022
MATHEMATICA
Select[Prime[Range[150]], Divisible[6^((#-1)/2)-3^((#-1)/2), #]&] (* Harvey P. Dale, Dec 25 2021 *)
PROG
(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
CROSSREFS
Sequence in context: A374482 A277213 A152451 * A118940 A127175 A339943
KEYWORD
nonn,easy
AUTHOR
Cino Hilliard, Sep 06 2004
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
STATUS
approved