First differences of A129983.

Terms

a(0) =0a(1) =1a(2) =3a(3) =7a(4) =15a(5) =31a(6) =64a(7) =134a(8) =285a(9) =613a(10) =1327a(11) =2883a(12) =6280a(13) =13716a(14) =30045a(15) =66019a(16) =145515a(17) =321675a(18) =713016a(19) =1584354a(20) =3528433a(21) =7874133a(22) =17605019a(23) =39428487a(24) =88441264a(25) =198658216a(26) =446791385a(27) =1005991171a(28) =2267376847a(29) =5115015303