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A255838
Smallest base-b Wieferich prime larger than b, where b = prime(n).
0
1093, 11, 20771, 491531, 71, 863, 46021, 43, 2481757
OFFSET
1,1
COMMENTS
a(10), if it exists, is larger than approximately 5.9*10^13, corresponding to the first odd Wieferich prime in base 29 (see Fischer link).
PROG
(PARI) forprime(b=1, 20, forprime(p=b, , if(Mod(b, p^2)^(p-1)==1, print1(p, ", "); break({1}))))
CROSSREFS
Cf. A247072.
Sequence in context: A271100 A258368 A174422 * A253234 A138698 A342390
KEYWORD
nonn,hard,more
AUTHOR
Felix Fröhlich, Mar 07 2015
STATUS
approved