a(n) = the number of ways that at least two distinct primes <= prime(n) sum to a prime.

Terms

a(0) =1a(1) =2a(2) =3a(3) =7a(4) =14a(5) =28a(6) =57a(7) =113a(8) =227a(9) =437a(10) =834a(11) =1616a(12) =3143a(13) =6144a(14) =12036a(15) =23467a(16) =45713a(17) =89375a(18) =175722a(19) =346193a(20) =681828a(21) =1344815a(22) =2657630a(23) =5253615a(24) =10374965a(25) =20471599a(26) =40401901a(27) =79871358a(28) =158182869a(29) =313402574