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A339537
Numbers b > 1 such that the smallest eight primes, i.e., 2, 3, 5, 7, 11, 13, 17 and 19 are base-b Wieferich primes.
6
126664001, 133487693, 141313157, 236176001, 242883757, 356977349, 358254649, 383691493
OFFSET
1,1
PROG
(PARI) is(n) = forprime(p=1, 19, if(Mod(n, p^2)^(p-1)!=1, return(0))); 1
CROSSREFS
Cf. A256236. Row 1 of A319065.
Cf. smallest k primes are base-b Wieferich primes: A339531 (k=2), A339532 (k=3), A339533 (k=4), A339534 (k=5), A339535 (k=6), A339536 (k=7).
Sequence in context: A227151 A227274 A162450 * A319065 A344832 A334346
KEYWORD
nonn,more
AUTHOR
Felix Fröhlich, Dec 08 2020
STATUS
approved