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A325881 Bases b where exactly five primes p with p < b exist such that p is a base-b Wieferich prime. 9
99, 161, 226, 293, 313, 424, 521, 557, 577, 606, 632, 649, 753, 757, 821, 874, 901, 925, 937, 1030, 1033, 1081, 1108, 1116, 1149, 1342, 1443, 1457, 1524, 1549, 1557, 1586, 1618, 1668, 1777, 1921, 1927, 1929, 1993, 2039, 2060, 2061, 2069, 2077, 2098, 2141, 2269 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n such that A255920(n) = 5.

LINKS

Table of n, a(n) for n=1..47.

PROG

(PARI) is(n) = my(i=0); forprime(p=1, n-1, if(Mod(n, p^2)^(p-1)==1, i++)); i==5

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), A325882 (k=6), A325883 (k=7), A325884 (k=8), A325885 (k=9), A325886 (k=10).

Sequence in context: A165603 A095420 A064112 * A185498 A126230 A055164

Adjacent sequences:  A325878 A325879 A325880 * A325882 A325883 A325884

KEYWORD

nonn

AUTHOR

Felix Fröhlich, May 26 2019

STATUS

approved

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Last modified July 24 14:27 EDT 2021. Contains 346273 sequences. (Running on oeis4.)