OFFSET
0,3
COMMENTS
a(0) = 0 since 2^0 - 1 = 0 and 0 is nonprime, a(1) = 1 since 2^1 - 1 = 1 and 1 is nonprime, a(2) = 15 since 2^4 - 1 = 15 and 4 is nonprime, ...
CROSSREFS
KEYWORD
nonn
AUTHOR
Jani Melik, Mar 10 2009
STATUS
approved