OFFSET
1,4
LINKS
Vaclav Kotesovec, Table of n, a(n) for n = 1..380
EXAMPLE
G.f.: A(x) = x + x^2 + x^3 + 2*x^4 + 3*x^5 + 6*x^6 + 10*x^7 + 20*x^8 +...
where A(x) = x + A(x^2 + B(x));
B(x) = A(x^3 + C(x)) = x^3 + x^4 + x^5 + 2*x^6 + 3*x^7 + 5*x^8 + 8*x^9 + 13*x^10 + 21*x^11 + 36*x^12 +...;
C(x) = A(x^4 + D(x)) = x^4 + x^5 + x^6 + x^7 + x^8 + x^9 + 2*x^10 + 3*x^11 + 5*x^12 + 7*x^13 + 10*x^14 +...;
D(x) = A(x^5 + E(x)) = x^5 + x^6 + x^7 + x^8 + x^9 + x^10 + x^11 + 2*x^12 + 3*x^13 + 5*x^14 + 7*x^15 + 10*x^16 +...;
E(x) = A(x^6 + F(x)) = x^6 + x^7 + x^8 + x^9 + x^10 + x^11 + x^12 + x^13 + 2*x^14 + 3*x^15 + 5*x^16 + 7*x^17 + 10*x^18 +...; ...
PROG
(PARI) {a(n)=local(G=x+x^2, A=G); for(i=1, n+1, A=G; G=x^(n+1); for(m=0, n, G=x^(n-m+1)+subst(A, x, G+x*O(x^n)))); polcoeff(A, n)}
for(n=0, 50, print1(a(n), ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Sep 05 2013
STATUS
approved