A255204 - OEIS

%I #8 Mar 07 2015 15:33:05

%S 29,37,43,59,79,97,103,109,113,137,151,181,191,197,199,223,233,241,

%T 257,263,281,283,293,307,373,379,397,401,419,421,433,439,449,461,499,

%U 521,523,547,557,563,577,601,617,619,641,659,661,701,727,739,743,761,769

%N Primes p for which exactly one base b with 1 < b < p exists such that p is a base b Wieferich prime.

%C p = prime(n) such that A242830(n) = 1.

%o (PARI) forprime(p=1, , b=2; i=0; while(b < p, if(Mod(b, p^2)^(p-1)==1, i++); b++); if(i==1, print1(p, ", ")))

%Y Cf. A255203, A255205, A255206, A255207, A255208, A255209, A255210.

%K nonn

%O 1,1

%A _Felix Fröhlich_, Feb 17 2015