Numbers k such that 2*5^k + 1 is prime.

Terms

a(0) =0a(1) =1a(2) =3a(3) =13a(4) =45a(5) =105a(6) =159a(7) =297a(8) =1443a(9) =2977a(10) =3699a(11) =11709a(12) =12357a(13) =43165a(14) =121995