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A030054 a(n) = binomial(2n+1,n-4). 4
1, 11, 78, 455, 2380, 11628, 54264, 245157, 1081575, 4686825, 20030010, 84672315, 354817320, 1476337800, 6107086800, 25140840660, 103077446706, 421171648758, 1715884494940, 6973199770790, 28277527346376 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,2

LINKS

Table of n, a(n) for n=4..24.

Milan Janjic, Two Enumerative Functions

FORMULA

G.f.: x^4*512/((1-sqrt(1-4*x))^9*sqrt(1-4*x))+(-1/x^5+7/x^4-15/x^3+10/x^2-1/x). - Vladimir Kruchinin, Aug 11 2015

MATHEMATICA

Table[Binomial[2n+1, n-4], {n, 4, 40}]  (* Harvey P. Dale, Mar 31 2011 *)

PROG

(PARI) vector(30, n, m=n+4; binomial(2*m+1, m-4)) \\ Michel Marcus, Aug 11 2015

CROSSREFS

Diagonal 10 of triangle A100257.

Fifth unsigned column (s=4) of A113187. - Wolfdieter Lang, Oct 19 2012

Sequence in context: A206529 A118936 A041224 * A225896 A239437 A140542

Adjacent sequences:  A030051 A030052 A030053 * A030055 A030056 A030057

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified January 15 20:47 EST 2019. Contains 319184 sequences. (Running on oeis4.)