Generalized Gaussian-Mersenne primes (see below).

Terms

a(0) =5a(1) =13a(2) =29a(3) =37a(4) =41a(5) =61a(6) =109a(7) =113a(8) =397a(9) =1321a(10) =1429a(11) =1613a(12) =2113a(13) =14449a(14) =26317a(15) =246241a(16) =279073a(17) =312709a(18) =525313a(19) =4327489a(20) =7416361a(21) =29247661a(22) =47392381a(23) =107367629a(24) =536903681a(25) =1326700741a(26) =40388473189a(27) =118750098349a(28) =275415303169a(29) =415878438361