Partial sums of A027964.

Terms

a(0) =1a(1) =8a(2) =34a(3) =107a(4) =281a(5) =654a(6) =1397a(7) =2801a(8) =5353a(9) =9859a(10) =17643a(11) =30869a(12) =53062a(13) =89951a(14) =150833a(15) =250780a(16) =414210a(17) =680665a(18) =1114160a(19) =1818310a(20) =2960806a(21) =4813018a(22) =7814074a(23) =12674542a(24) =20544191a(25) =33283434a(26) =53902532a(27) =87272241a(28) =141273663a(29) =228658744