Euler transform of primes.

Terms

a(0) =1a(1) =2a(2) =6a(3) =15a(4) =37a(5) =85a(6) =192a(7) =414a(8) =879a(9) =1816a(10) =3694a(11) =7362a(12) =14480a(13) =28037a(14) =53644a(15) =101379a(16) =189587a(17) =350874a(18) =643431a(19) =1169388a(20) =2108045a(21) =3770430a(22) =6694894a(23) =11804968a(24) =20679720a(25) =35999794a(26) =62298755a(27) =107198541a(28) =183462856a(29) =312357002