OFFSET
0,5
COMMENTS
a(n) = (1 + Sum_{k=1..2*n} k^(2*n)) (mod 2*n+1), for n = 0, 1, 2, 3, ...
The Agoh-Giuga Conjecture is that a(n)=0 iff 2*n+1 is 1 or a prime.
LINKS
FORMULA
a(n) = 0 iff A235364(n) = 0.
MATHEMATICA
Table[ Mod[ Sum[ PowerMod[ k, n - 1, n], {k, n - 1}] + 1, n], {n, 1, 201, 2}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Jonathan Sondow, Jan 07 2014
STATUS
approved