Coefficient of x^n in solution of x = y + y^2 + y^4 + y^8 + ...

Terms

a(0) =1a(1) =-1a(2) =2a(3) =-6a(4) =20a(5) =-70a(6) =256a(7) =-970a(8) =3772a(9) =-14960a(10) =60280a(11) =-246090a(12) =1015700a(13) =-4231216a(14) =17767456a(15) =-75126078a(16) =319588340a(17) =-1366846548a(18) =5873832384a(19) =-25350152100a(20) =109828012448a(21) =-477486940848