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A211076
Least prime q such that k^p - p is not divisible by q for any positive integer k, where p is the n-th prime.
1
3, 7, 11, 17, 23, 31, 41, 31, 31, 53, 47, 53, 47, 59, 67, 89, 79, 83, 97, 101, 101, 101, 139, 113, 167, 127, 107, 151, 137, 149, 197, 157, 151, 149, 167, 239, 223, 229, 191, 211, 211, 239, 211, 277, 239, 251, 241, 313, 257, 251, 313, 307, 307, 347, 347, 347
OFFSET
1,1
COMMENTS
For p > 2 there is some prime dividing sigma(p^(p-1)) for which k^p - p is not divisible by the prime for any k. Thus a(n) exists and is at most sigma(p^(p-1)).
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..1000
PROG
(PARI) a(n)=my(p=prime(n)); forprime(q=2, default(primelimit), for(k=2, p, if(Mod(k, q)^p==p, next(2))); return(q)) \\ Charles R Greathouse IV, May 09 2012
CROSSREFS
Sequence in context: A188653 A333996 A262502 * A180452 A294479 A331968
KEYWORD
nonn
AUTHOR
STATUS
approved