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A263429
Smallest prime p such that binomial(2*p-1, p-1) == 1 (mod p^n), or 0 if no such p exists.
1
2, 3, 5, 16843
OFFSET
1,1
COMMENTS
For n > 1, smallest p = prime(i) such that A244919(i) = n.
For n > 3, p is a term of A088164.
Conjecture: a(n) = 0 for n > 4 (McIntosh, 1995, p. 387).
LINKS
R. J. McIntosh, On the converse of Wolstenholme's theorem, Acta Arithmetica, Vol. 71, No. 4 (1995), 381-389.
PROG
(PARI) a(n) = my(p=2); while(Mod(binomial(2*p-1, p-1), p^n)!=1, p=nextprime(p+1)); p
CROSSREFS
Sequence in context: A089678 A072712 A046476 * A175309 A357323 A335304
KEYWORD
nonn,hard,more,bref
AUTHOR
Felix Fröhlich, Oct 18 2015
STATUS
approved