p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - 2 S + S^3.

Terms

a(0) =2a(1) =6a(2) =15a(3) =37a(4) =89a(5) =212a(6) =500a(7) =1173a(8) =2741a(9) =6388a(10) =14860a(11) =34524a(12) =80138a(13) =185904a(14) =431075a(15) =999280a(16) =2315960a(17) =5366755a(18) =12435075a(19) =28810731a(20) =66748062a(21) =154635086a(22) =358234115a(23) =829886167a(24) =1922494024a(25) =4453566092a(26) =10316878400a(27) =23899399028a(28) =55363614076a(29) =128251081293