1,2
A subsequence of A050412.
Table of n, a(n) for n=1..8.
Cf. A050412, A051914, A052333, A052334, A052340.
Sequence in context: A032498 A144613 A031330 * A310562 A358577 A123076
Adjacent sequences: A052336 A052337 A052338 * A052340 A052341 A052342
nonn,hard
Christian G. Bower, Dec 23 1999
659*2^n-1 is composite for n<2^17.
One more term supplied by David Broadhurst, Jan 02 2000
approved