OFFSET
0,3
EXAMPLE
G.f.: A(x) = 1 + x + 2*x^2 + 10*x^3 + 77*x^4 + 771*x^5 + 9258*x^6 +...
Related expansions.
A(x)^2 = 1 + 2*x + 5*x^2 + 24*x^3 + 178*x^4 + 1736*x^5 + 20466*x^6 +...
A(x/A(x))^2 = 1 + 2*x + 3*x^2 + 12*x^3 + 87*x^4 + 848*x^5 + 10029*x^6 +...
A(x/A(x)) = 1 + x + x^2 + 5*x^3 + 38*x^4 + 381*x^5 + 4583*x^6 + 63303*x^7 + 977998*x^8 + 16617314*x^9 + 306942415*x^10 +...
PROG
(PARI) {a(n)=local(A=[1, 1]); for(i=1, n, A=concat(A, 0); (A[#A]=-Vec(subst(Ser(A)^2, x, x/Ser(A))/(1+x))[#A])); A[n+1]}
for(n=0, 30, print1(a(n), ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jul 21 2014
STATUS
approved