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%I #4 Nov 21 2019 22:16:17
%S 1,1,2,6,19,64,219,777,2803,10315,38496,145516,555764,2142060,8320207,
%T 32538518,128012533,506300507,2011932479,8028941336,32163411045,
%U 129291553211,521372223648,2108522273338,8549844313915,34753397386201,141584261960345
%N G.f. A(x) satisfies: A(x) = 1 / (1 - x * Product_{k>=1} A(x^k)).
%t nmax = 26; A[_] = 0; Do[A[x_] = 1/(1 - x Product[A[x^k], {k, 1, nmax}]) + O[x]^(nmax + 1) // Normal, nmax + 1]; CoefficientList[A[x], x]
%Y Cf. A050383, A091865.
%K nonn
%O 0,3
%A _Ilya Gutkovskiy_, Nov 21 2019