First terms from generation 1 onwards.

Terms

a(0) =2a(1) =3a(2) =7a(3) =13a(4) =30a(5) =56a(6) =127a(7) =237a(8) =530a(9) =994a(10) =2192a(11) =4144a(12) =9016a(13) =17192a(14) =36949a(15) =71023a(16) =151024a(17) =292340a(18) =616032a(19) =1199556a(20) =2508660a(21) =4909028a(22) =10201810a(23) =20044004a(24) =41437560a(25) =81683022a(26) =168134730a(27) =332321130a(28) =681582636a(29) =1350091410