1,1

Base 14 Wieferich primes.

Table of n, a(n) for n=1..3.

Petr Ležák, Solutions of equation a^(p-1) mod p^2 = 1, p is prime

P. L. Montgomery, New solutions of a^p-1 == 1 (mod p^2), Math. Comp., 61 (203), 361-363

Select[Prime[Range[200]], Divisible[14^(# - 1) - 1, #^2] &] (* Alonso del Arte, Apr 20 2014 *)

(PARI)

N=10^9; default(primelimit, N);

forprime(n=2, N, if(Mod(14, n^2)^(n-1)==1, print1(n, ", ")));

Cf. A001220.

Sequence in context: A156640 A239743 A022689 * A077516 A142278 A281059

Adjacent sequences:  A234807 A234808 A234809 * A234811 A234812 A234813

nonn,hard,bref,more

Felix Fröhlich, Apr 19 2014

approved