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A325882 Bases b where exactly six primes p with p < b exist such that p is a base-b Wieferich prime. 9
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 (list; graph; refs; listen; history; text; internal format)
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: A003799 A003930 A137607 * A255787 A219340 A183997

Adjacent sequences:  A325879 A325880 A325881 * A325883 A325884 A325885

KEYWORD

nonn

AUTHOR

Felix Fröhlich, May 26 2019

STATUS

approved

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Last modified July 24 14:21 EDT 2021. Contains 346273 sequences. (Running on oeis4.)