OFFSET
0,1
COMMENTS
For any k >= 1, numbers of the form (k*a(n) + k - 1)*2^m - 1 are composite for all m < 2^(n+1).
Many terms are in common with A006285 (de Polignac numbers).
PROG
(PARI) a(n) = - 1 + 2 * prod(k=0, n, factor(2^(2^k)+1)[1, 1]); \\ Michel Marcus, Jul 04 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
Arkadiusz Wesolowski, Jul 02 2015
STATUS
approved