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A027439 Expansion of 1/(1 - 4*x + 5*x^2 - 3*x^3). 0
1, 4, 11, 27, 65, 158, 388, 957, 2362, 5827, 14369, 35427, 87344, 215348, 530953, 1309104, 3227695, 7958119, 19621313, 48377742, 119278760, 294090269, 725100502, 1787786943, 4407916069, 10868031067 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Number of ordered trees with n+3 edges having on each subtree of the root exactly one node with more than one descendant. - Emeric Deutsch, Dec 11 2007

LINKS

Table of n, a(n) for n=0..25.

MAPLE

G:=1/(1-4*x+5*x^2-3*x^3): Gser:=series(G, x=0, 30): seq(coeff(Gser, x, n), n=0.. 25); # Emeric Deutsch, Dec 11 2007

CROSSREFS

Sequence in context: A080869 A137229 A301874 * A108985 A014151 A176759

Adjacent sequences:  A027436 A027437 A027438 * A027440 A027441 A027442

KEYWORD

nonn,changed

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified May 25 15:22 EDT 2019. Contains 323572 sequences. (Running on oeis4.)