p-INVERT of the positive integers, where p(S) = 1 - S^2.

Terms

a(0) =0a(1) =1a(2) =4a(3) =11a(4) =28a(5) =72a(6) =188a(7) =493a(8) =1292a(9) =3383a(10) =8856a(11) =23184a(12) =60696a(13) =158905a(14) =416020a(15) =1089155a(16) =2851444a(17) =7465176a(18) =19544084a(19) =51167077a(20) =133957148a(21) =350704367a(22) =918155952a(23) =2403763488a(24) =6293134512a(25) =16475640049a(26) =43133785636a(27) =112925716859a(28) =295643364940a(29) =774004377960