G.f.: exp( Sum_{n>=1} x^n/n * exp( Sum_{k>=1} binomial(2*n*k,n*k)*x^(n*k)/k ) ).

A205503

G.f.: exp( Sum_{n>=1} x^n/n * exp( Sum_{k>=1} binomial(2*n*k,n*k)*x^(n*k)/k ) ).

Terms

    a(0) =1a(1) =1a(2) =3a(3) =8a(4) =27a(5) =79a(6) =292a(7) =900a(8) =3369a(9) =11131a(10) =41742a(11) =139002a(12) =546529a(13) =1829265a(14) =7113275a(15) =24903332a(16) =96838366a(17) =335955634a(18) =1345392796a(19) =4673507879a(20) =18615675149a(21) =66574809640a(22) =262503701044a(23) =933024442958

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