OFFSET
1,1
LINKS
J. M. Grau and A. M. Oller-Marcén, On the congruence sum_{j=1}^{n-1} j^{k(n-1)} == -1 (mod n); k-strong Giuga and k-Carmichael numbers, arXiv preprint arXiv:1311.3522, 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jan 12 2014
STATUS
approved