Primes p of the form sigma(2q-1) where q is a prime.

Terms

a(0) =13a(1) =31a(2) =2801a(3) =3541a(4) =5113a(5) =10303a(6) =17293a(7) =30941a(8) =88741a(9) =292561a(10) =732541a(11) =1191373a(12) =1395943a(13) =2922391a(14) =3281533a(15) =7450171a(16) =7781311a(17) =12190573a(18) =15916111a(19) =22292563a(20) =28792661a(21) =67757593a(22) =93886411a(23) =103052953a(24) =112137511a(25) =124802413a(26) =135059263a(27) =181427431