A211827 G.f. satisfies: A(x) = x + x^2 * A'(A(x)).

1, 1, 2, 8, 48, 382, 3756, 43756, 587624, 8924812, 151144684, 2823121164, 57649783664, 1277765175416, 30551583576144, 783907809051392, 21486223682939760, 626575942278440112, 19371271089840844552, 632894233658705820660, 21789691181582852824488

Offset

0,3

Links

Table of n, a(n) for n=0..20.

Example

 G.f.: A(x) = x + x^2 + 2*x^3 + 8*x^4 + 48*x^5 + 382*x^6 + 3756*x^7 +...
Related expansions:
A'(x) = 1 + 2*x + 6*x^2 + 32*x^3 + 240*x^4 + 2292*x^5 + 26292*x^6 +...
A(A(x)) = x + 2*x^2 + 6*x^3 + 27*x^4 + 166*x^5 + 1306*x^6 + 12556*x^7 +...

Prog

 (PARI) {a(n)=local(A=x+x^2+x*O(x^n)); for(i=1, n, A=x+x^2*subst(A', x, A)); polcoeff(A, n)}
for(n=1, 21, print1(a(n), ", "))

Crossrefs

Cf. A211828.

Sequence in context: A334856 A219613 A124453 * A360582 A322339 A000165

Adjacent sequences: A211824 A211825 A211826 * A211828 A211829 A211830

Keyword

nonn

Author

Paul D. Hanna, Apr 21 2012

Status

approved