G.f. satisfies A(x) = exp( Sum_{k>=1} (-1)^(k+1) * A(x^k) * (2*x)^k/k ).

A363441

G.f. satisfies A(x) = exp( Sum_{k>=1} (-1)^(k+1) * A(x^k) * (2*x)^k/k ).

Terms

    a(0) =1a(1) =2a(2) =4a(3) =16a(4) =52a(5) =208a(6) =840a(7) =3520a(8) =15008a(9) =65344a(10) =288408a(11) =1288416a(12) =5813744a(13) =26460800a(14) =121333200a(15) =559991712a(16) =2599385536a(17) =12127405952a(18) =56837861376a(19) =267473333120

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