G.f. satisfies A(x) = ( 1 + x*A(x)^2 / (1 - x*A(x)) )^2.

A365146

G.f. satisfies A(x) = ( 1 + x*A(x)^2 / (1 - x*A(x)) )^2.

Terms

    a(0) =1a(1) =2a(2) =11a(3) =76a(4) =591a(5) =4938a(6) =43297a(7) =393006a(8) =3661500a(9) =34813530a(10) =336447364a(11) =3295264162a(12) =32636826276a(13) =326310118860

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