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

A138020

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

Terms

    a(0) =1a(1) =2a(2) =6a(3) =24a(4) =110a(5) =544a(6) =2828a(7) =15232a(8) =84246a(9) =475648a(10) =2730068a(11) =15882240a(12) =93438540a(13) =554967040a(14) =3323125528a(15) =20039827456a(16) =121597985254a(17) =741871845376

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