Revert transform of 2*x*(1 - x - x^5 + x^6)-x/(1+x).

Terms

a(0) =1a(1) =1a(2) =3a(3) =9a(4) =33a(5) =127a(6) =517a(7) =2171a(8) =9359a(9) =41139a(10) =183749a(11) =831479a(12) =3803859a(13) =17563853a(14) =81747331a(15) =383116181a(16) =1806427061a(17) =8563227837a(18) =40787427055a(19) =195106310221a(20) =936890791253