Cullen numbers: a(n) = n*2^n + 1.

Terms

a(0) =1a(1) =3a(2) =9a(3) =25a(4) =65a(5) =161a(6) =385a(7) =897a(8) =2049a(9) =4609a(10) =10241a(11) =22529a(12) =49153a(13) =106497a(14) =229377a(15) =491521a(16) =1048577a(17) =2228225a(18) =4718593a(19) =9961473a(20) =20971521a(21) =44040193a(22) =92274689a(23) =192937985a(24) =402653185a(25) =838860801a(26) =1744830465a(27) =3623878657a(28) =7516192769a(29) =15569256449