G.f. satisfies: A(x) = Sum_{n>=0} x^n * A(x)^(n*(n+1)/2) / Product_{k=1..n} (1 + x*A(x)^k).

A221586

G.f. satisfies: A(x) = Sum_{n>=0} x^n * A(x)^(n*(n+1)/2) / Product_{k=1..n} (1 + x*A(x)^k).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =2a(4) =5a(5) =14a(6) =43a(7) =140a(8) =478a(9) =1695a(10) =6205a(11) =23356a(12) =90135a(13) =355960a(14) =1436755a(15) =5922799a(16) =24929035a(17) =107136291a(18) =470281976a(19) =2109608447a(20) =9677546281a(21) =45434467501a(22) =218478232454

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