Primes of the form 2^(k-1)*k^2-(-1)^k.

Terms

a(0) =2a(1) =7a(2) =37a(3) =127a(4) =401a(5) =1151a(6) =3137a(7) =8191a(8) =51199a(9) =294911a(10) =1605631a(11) =3686401a(12) =209715199a(13) =10485760001