a(n) = A129150(n) / 4, where A129150(n) = n-th arithmetic derivative of 2^3.

Terms

a(0) =2a(1) =3a(2) =4a(3) =8a(4) =20a(5) =44a(6) =92a(7) =188a(8) =380a(9) =856a(10) =2148a(11) =5024a(12) =17616a(13) =58768a(14) =176320a(15) =755904a(16) =3305920a(17) =13885184a(18) =69634816a(19) =348174336a(20) =2385273856a(21) =14652403712a(22) =102566830080a(23) =849285738496