Coefficient of x^n in A(x)^n is A087457(n) for n>=1.

Terms

a(0) =1a(1) =1a(2) =2a(3) =6a(4) =23a(5) =102a(6) =497a(7) =2586a(8) =14121a(9) =80006a(10) =466658a(11) =2786516a(12) =16963465a(13) =104952998a(14) =658331520a(15) =4178564242a(16) =26795934011a(17) =173388619910