cp's OEIS Frontend

A155928 G.f. satisfies: A(x) = F(x)^2 where F(x) = Sum_{n>=0} A155926(n)*x^n/[n!*(n+1)!/2^n] and A(x) = Sum_{n>=0} a(n)*x^n/[n!*(n+1)!/2^n].

%I A155928 #2 Mar 30 2012 18:37:16
%S A155928 1,2,11,122,2302,66482,2735721,152359874,11048880926,1012437290342,
%T A155928 114445632250776,15649612498128050,2546878326578431588,
%U A155928 486567378291992448726,107845834421517755737817
%N A155928 G.f. satisfies: A(x) = F(x)^2 where F(x) = Sum_{n>=0} A155926(n)*x^n/[n!*(n+1)!/2^n] and A(x) = Sum_{n>=0} a(n)*x^n/[n!*(n+1)!/2^n].
%F A155928 G.f. satisfies: A(x) = B( x*sqrt(A(x)) )^2 where B(x) = Sum_{n>=0} x^n/[n!*(n+1)!/2^n].
%e A155928 G.f.: A(x) = 1 + 2*x + 11*x^2/3 + 122*x^3/18 + 2302*x^4/180 + 66482*x^5/2700 +...
%e A155928 G.f.: A(x) = F(x)^2 where:
%e A155928 F(x) = 1 + x + 4*x^2/3 + 37*x^3/18 + 621*x^4/180 + 16526*x^5/2700 +...+ A155926(n)*x^n/[n!*(n+1)!/2^n] +...
%e A155928 G.f. satisfies: A(x) = B( x*sqrt(A(x)) )^2 where:
%e A155928 B(x) = 1 + x + x^2/3 + x^3/18 + x^4/180 + x^5/2700 +...+ x^n/[n!*(n+1)!/2^n] +...
%o A155928 (PARI) {a(n)=local(B=sum(k=0,n,x^k/(k!*(k+1)!/2^k))+x*O(x^n));polcoeff((serreverse(x/B)/x)^2,n)*n!*(n+1)!/2^n}
%Y A155928 Cf. A155926.
%K A155928 nonn
%O A155928 0,2
%A A155928 _Paul D. Hanna_, Jan 31 2009