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A325884 Bases b where exactly eight primes p with p < b exist such that p is a base-b Wieferich prime. 9
1693, 5937, 8201, 9035, 9066, 12943, 13499, 14773, 19065, 24841, 25298, 27382, 28601, 28657, 32074, 37993, 39789, 40276, 41749, 42893, 44425, 46307, 46657, 46924, 47899, 49099, 50471, 52757, 53576, 55737, 56026, 56193, 56645, 57221, 57853, 58445, 59216, 59249 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n such that A255920(n) = 8.

LINKS

Table of n, a(n) for n=1..38.

PROG

(PARI) is(n) = my(i=0); forprime(p=1, n-1, if(Mod(n, p^2)^(p-1)==1, i++)); i==8

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), A325882 (k=6), A325883 (k=7), A325885 (k=9), A325886 (k=10).

Sequence in context: A089674 A252429 A126720 * A224605 A252570 A235182

Adjacent sequences:  A325881 A325882 A325883 * A325885 A325886 A325887

KEYWORD

nonn

AUTHOR

Felix Fröhlich, May 26 2019

STATUS

approved

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Last modified January 16 00:05 EST 2021. Contains 340195 sequences. (Running on oeis4.)