OFFSET
0,3
EXAMPLE
G.f.: A(x) = 1 + x + 2*x^2 + 13*x^3 + 174*x^4 + 4232*x^5 + 182382*x^6 +...
Related expansions:
A(x)^2 = 1 + 2*x + 5*x^2 + 30*x^3 + 378*x^4 + 8864*x^5 + 374093*x^6 +...
A(A(x)^2 - 1) = 1 + 2*x + 13*x^2 + 174*x^3 + 4232*x^4 + 182382*x^5 +...
PROG
(PARI) {a(n)=local(A=1+x+x*O(x^n)); for(i=1, n, A=1+x*subst(A, x, A^2-1+x*O(x^n))); polcoeff(A, n)}
for(n=0, 25, print1(a(n), ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Apr 24 2012
STATUS
approved