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A255208 Primes p for which exactly five bases b with 1 < b < p exist such that p is a base b Wieferich prime. 8
653, 4909, 7723, 9811, 13691, 15413, 18133, 18223, 21061, 22147, 25679, 29131, 33923, 35353, 36913, 37633, 46021, 57527, 61819, 66107, 71059, 72643, 77867, 79867, 85061, 87509, 89113, 96757, 97213, 98641, 117977, 118163, 120247, 122209, 123653, 126443, 129061 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

p = prime(n) such that A242830(n) = 5.

LINKS

Table of n, a(n) for n=1..37.

PROG

(PARI) forprime(p=1, , b=2; i=0; while(b < p, if(Mod(b, p^2)^(p-1)==1, i++); b++); if(i==5, print1(p, ", ")))

CROSSREFS

Cf. A255203, A255204, A255205, A255206, A255207, A255209, A255210.

Sequence in context: A145125 A145202 A188366 * A060520 A250701 A250158

Adjacent sequences:  A255205 A255206 A255207 * A255209 A255210 A255211

KEYWORD

nonn

AUTHOR

Felix Fröhlich, Feb 17 2015

STATUS

approved

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Last modified December 6 06:14 EST 2021. Contains 349563 sequences. (Running on oeis4.)