Generating function satisfies A(x)=1-xA(x)+2x(A(x))^2-x^2(A(x))^3+x^2(A(x))^4.

A200740

Generating function satisfies A(x)=1-xA(x)+2x(A(x))^2-x^2(A(x))^3+x^2(A(x))^4.

Terms

    a(0) =1a(1) =1a(2) =3a(3) =12a(4) =54a(5) =261a(6) =1324a(7) =6954a(8) =37493a(9) =206316a(10) =1154050a(11) =6542485a(12) =37507919a(13) =217081155a(14) =1266646114a(15) =7443100944a(16) =44008522719a(17) =261631301144

External references