cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A132055 Tenth column of triangle A035342.

Original entry on oeis.org

1, 165, 16665, 1349205, 97026930, 6526750230, 423076603950, 26922666320550, 1702498733310375, 107876426221438875, 6888889247523458175, 445180690239692281875, 29198763785973826044000
Offset: 10

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Author

Wolfdieter Lang Sep 14 2007

Keywords

Comments

a(n), n>=10, enumerates unordered forests composed of nine plane ternary trees with n vertices. See A001147 (number of increasing ternary trees) and a D. Callan comment there. For a picture of some ternary trees see a W. Lang link under A001764.
a(n), n>=10, enumerates unordered forests composed of ten plane increasing ternary trees with n vertices. See A001147 (number of increasing ternary trees) and a D. Callan comment there. For a picture of some ternary trees see a W. Lang link under A001764.

Examples

			a(11)=165=3*binomial(11,2) increasing ternary 10-forest with n=11 vertices: there are three 10-forests (nine one vertex trees together with any of the three different 2-vertex trees) each with binomial(11,2)= 55 increasing labelings.

Crossrefs

Cf. A132054 (eighth column).

Formula

E.g.f.: ((x*c(x/2)*(1-2*x)^(-1/2))^10)/10!, where c(x) = g.f. for Catalan numbers A000108, a(0) := 0.
E.g.f.: (-1+(1-2*x)^(-1/2))^10/10!.
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Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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