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 A199104 G.f. satisfies: A(x) = exp( Sum(n>=1} A(x^n)/(1-x)^n * x^n/n ). 1

%I

%S 1,1,3,9,28,88,284,931,3109,10532,36162,125546,440201,1556519,5544715,

%T 19879791,71685522,259809731,945913555,3457947627,12687782600,

%U 46709518473,172484216742,638712762962,2371241532557,8824154454401,32909438791706,122984173008460

%N G.f. satisfies: A(x) = exp( Sum(n>=1} A(x^n)/(1-x)^n * x^n/n ).

%e G.f.: A(x) = 1 + x + 3*x^2 + 9*x^3 + 28*x^4 + 88*x^5 + 284*x^6 + 931*x^7 +...

%e where

%e log(A(x)) = A(x)/(1-x)*x + A(x^2)/(1-x)^2*x^2/2 + A(x^3)/(1-x)^3*x^3/3 +...

%o (PARI) {a(n)=local(A=1+x);for(i=1,n,A=exp(sum(m=1,n,(1-x)^-m*x^m/m*subst(A,x,x^m+x*O(x^n)))));polcoeff(A,n)}

%Y Cf. A199103.

%K nonn

%O 0,3

%A _Paul D. Hanna_, Nov 03 2011

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Last modified September 20 05:51 EDT 2019. Contains 327212 sequences. (Running on oeis4.)