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A248865 Primes p that set a new record for the number of bases 1 < b < p for which p is a base-b Wieferich prime. 4
2, 11, 269, 487, 653, 1093, 3511, 1006003 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes p where A242830(i) reaches record values, where i is the index of p in A000040.

The corresponding number of bases are 0, 2, 3, 4, 5, 10, 11, 12. - Jianing Song, Feb 07 2019

LINKS

Table of n, a(n) for n=1..8.

PROG

(PARI) my(r=-1); forprime(p=2, , my(b=2, i=0); while(b < p, if(Mod(b, p^2)^(p-1)==1, i++); b++); if(i > r, print1(p, ", "); r=i)) \\ changed to include a(1) = 2 by Jianing Song, Feb 07 2019

CROSSREFS

Cf. A000040, A175932, A242830.

Subsequence of A175932. Apart from the first term, subsequence of A134307.

Sequence in context: A134096 A132571 A102031 * A072386 A185122 A198894

Adjacent sequences:  A248862 A248863 A248864 * A248866 A248867 A248868

KEYWORD

nonn,hard,more

AUTHOR

Felix Fröhlich, Mar 07 2015

EXTENSIONS

a(1) = 2 inserted by Jianing Song, Feb 07 2019

STATUS

approved

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Last modified July 5 01:22 EDT 2020. Contains 335457 sequences. (Running on oeis4.)