OFFSET
0,3
LINKS
Paul D. Hanna, Table of n, a(n) for n = 0..200
EXAMPLE
G.f.: A(x) = 1 + x + 2*x^2 + 5*x^3 + 22*x^4 + 100*x^5 + 581*x^6 + 3716*x^7 + 26352*x^8 + 203664*x^9 + 1688485*x^10 + 14922599*x^11 + 139579911*x^12 + ...
such that
A(x) = 1 + x*(1+x)^2/A(x) + x^2*(1+x)^8/A(x)^2 + x^3*(1+x)^18/A(x)^3 + x^4*(1+x)^32/A(x)^4 + x^5*(1+x)^50/A(x)^5 + x^6*(1+x)^72/A(x)^6 + ...
PROG
(PARI) {a(n) = my(A=[1]); for(i=1, n, A = concat(A, 0); A[#A] = Vec(sum(n=0, #A, ((1+x)^n +x*O(x^#A))^(2*n) * x^n/Ser(A)^(n+1) ) )[#A] ); A[n+1]}
for(n=0, 30, print1(a(n), ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Nov 23 2018
STATUS
approved