A219260 G.f. satisfies: A(x) = exp(Sum_{n>=1} x^n*A(x)^n/n * Product_{k>=1} (1 + x^(n*k)*A(x^k)^n)).

1, 1, 3, 10, 37, 143, 576, 2393, 10178, 44133, 194341, 866867, 3908454, 17784385, 81562890, 376637216, 1749704080, 8171760933, 38346326963, 180707395127, 854850922373, 4057990958069, 19324260613400, 92288612451684, 441919933724974, 2121281845071105, 10205443975074195

Offset

0,3

Comments

Compare to the dual g.f. G(x) of A219261:

G(x) = exp(Sum_{n>=1} x^n*G(x^n)/n * Product_{k>=1} (1+x^(n*k)*G(x^n)^k)).

Links

Table of n, a(n) for n=0..26.

Example

G.f.: A(x) = 1 + x + 3*x^2 + 10*x^3 + 37*x^4 + 143*x^5 + 576*x^6 + 2393*x^7 +...
where
log(A(x)) = x*A(x)/1*((1+x*A(x))*(1+x^2*A(x^2))*(1+x^3*A(x^3))*...) +
x^2*A(x)^2/2*((1+x^2*A(x)^2)*(1+x^4*A(x^2)^2)*(1+x^6*A(x^3)^2)*...) +
x^3*A(x)^3/3*((1+x^3*A(x)^3)*(1+x^6*A(x^2)^3)*(1+x^9*A(x^3)^3)*...) +
x^4*A(x)^4/4*((1+x^4*A(x)^4)*(1+x^8*A(x^2)^4)*(1+x^12*A(x^3)^4)*...) +...
Explicitly,
log(A(x)) = x + 5*x^2/2 + 22*x^3/3 + 101*x^4/4 + 461*x^5/5 + 2144*x^6/6 + 10109*x^7/7 + 48117*x^8/8 + 230998*x^9/9 + 1115875*x^10/10 +...

Prog

(PARI) {a(n)=local(A=1+x); for(i=1, n, A=exp(sum(m=1, n, x^m*A^m/m*prod(k=1, n\m+1, 1+x^(m*k)*subst(A^m, x, x^k +x*O(x^n)))))); polcoeff(A, n)}
for(n=0, 30, print1(a(n), ", "))

Crossrefs

Cf. A218552, A219262, A219261, A218153.

Sequence in context: A105284 A211975 A357399 * A151050 A151051 A164044

Adjacent sequences: A219257 A219258 A219259 * A219261 A219262 A219263

Keyword

nonn

Author

Paul D. Hanna, Nov 16 2012

Status

approved