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

Terms

a(0) =2a(1) =7a(2) =18a(3) =55a(4) =144a(5) =404a(6) =1060a(7) =2853a(8) =7442a(9) =19573a(10) =50670a(11) =131368a(12) =337622a(13) =866819a(14) =2213650a(15) =5642899a(16) =14332988a(17) =36335548a(18) =91872760a(19) =231875713a(20) =584030738a(21) =1468631153a(22) =3686943130a(23) =9242753104a(24) =23138167146a(25) =57851432575a(26) =144470316562a(27) =360384852207a(28) =898051760168