A325882 Bases b where exactly six primes p with p < b exist such that p is a base-b Wieferich prime.

361, 476, 699, 977, 1121, 1145, 1293, 1667, 1745, 1868, 2157, 2382, 2468, 2665, 2793, 2897, 3038, 3149, 3526, 4033, 4643, 4746, 4789, 5032, 5073, 5567, 5651, 5660, 5777, 5824, 6205, 6320, 6346, 6377, 6421, 6732, 6769, 6949, 6957, 6976, 7318, 7669, 7793, 7937

Offset

1,1

Comments

Numbers n such that A255920(n) = 6.

Links

Table of n, a(n) for n=1..44.

Prog

(PARI) is(n) = my(i=0); forprime(p=1, n-1, if(Mod(n, p^2)^(p-1)==1, i++)); i==6

Crossrefs

Cf. A255920.

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), A325883 (k=7), A325884 (k=8), A325885 (k=9), A325886 (k=10).

Sequence in context: A003930 A137607 A367792 * A255787 A219340 A183997

Adjacent sequences: A325879 A325880 A325881 * A325883 A325884 A325885

Keyword

nonn

Author

Felix Fröhlich, May 26 2019

Status

approved