Expansion of (1/x) * Series_Reversion( x * (1 - x^2 / (1 - x)^4) ).

Terms

a(0) =1a(1) =0a(2) =1a(3) =4a(4) =13a(5) =48a(6) =191a(7) =776a(8) =3219a(9) =13628a(10) =58600a(11) =255124a(12) =1122519a(13) =4983796a(14) =22299627a(15) =100454036a(16) =455212313a(17) =2073680196a(18) =9490802309a(19) =43620240660a(20) =201241963152a(21) =931624173296