a(n) = 2^n+n^3.

Terms

a(0) =1a(1) =3a(2) =12a(3) =35a(4) =80a(5) =157a(6) =280a(7) =471a(8) =768a(9) =1241a(10) =2024a(11) =3379a(12) =5824a(13) =10389a(14) =19128a(15) =36143a(16) =69632a(17) =135985a(18) =267976a(19) =531147a(20) =1056576a(21) =2106413a(22) =4204952a(23) =8400775a(24) =16791040a(25) =33570057a(26) =67126440a(27) =134237411a(28) =268457408a(29) =536895301