a(n) = 110*2^n + 118.

Terms

a(0) =228a(1) =338a(2) =558a(3) =998a(4) =1878a(5) =3638a(6) =7158a(7) =14198a(8) =28278a(9) =56438a(10) =112758a(11) =225398a(12) =450678a(13) =901238a(14) =1802358a(15) =3604598a(16) =7209078a(17) =14418038a(18) =28835958a(19) =57671798a(20) =115343478a(21) =230686838a(22) =461373558a(23) =922746998a(24) =1845493878a(25) =3690987638a(26) =7381975158a(27) =14763950198a(28) =29527900278a(29) =59055800438