First differences of A045891.

Terms

a(0) =1a(1) =0a(2) =2a(3) =4a(4) =9a(5) =20a(6) =44a(7) =96a(8) =208a(9) =448a(10) =960a(11) =2048a(12) =4352a(13) =9216a(14) =19456a(15) =40960a(16) =86016a(17) =180224a(18) =376832a(19) =786432a(20) =1638400a(21) =3407872a(22) =7077888a(23) =14680064a(24) =30408704a(25) =62914560a(26) =130023424a(27) =268435456a(28) =553648128a(29) =1140850688