A325886 - OEIS

%I #4 May 26 2019 15:01:24

%S 13834,73837,151325,172324,182973,213615,233009,275786,283877,296449

%N Bases b where exactly ten primes p with p < b exist such that p is a base-b Wieferich prime.

%C Numbers n such that A255920(n) = 10.

%o (PARI) is(n) = my(i=0); forprime(p=1, n-1, if(Mod(n, p^2)^(p-1)==1, i++)); i==10

%Y Cf. A255920.

%Y Cf. bases b with exactly k base-b Wieferich primes less than b: A255921 (k=0), A255922 (k=1), A255923 (k=2), A255924 (k=3), A255925 (k=4), A325881 (k=5), A325882 (k=6), A325883 (k=7), A325884 (k=8), A325885 (k=9).

%K nonn,more

%O 1,1

%A _Felix Fröhlich_, May 26 2019