Sum of first n primes minus next prime.

Terms

a(0) =-1a(1) =0a(2) =3a(3) =6a(4) =15a(5) =24a(6) =39a(7) =54a(8) =71a(9) =98a(10) =123a(11) =156a(12) =195a(13) =234a(14) =275a(15) =322a(16) =379a(17) =434a(18) =497a(19) =566a(20) =633a(21) =708a(22) =785a(23) =866a(24) =959a(25) =1058a(26) =1157a(27) =1262a(28) =1367a(29) =1466