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A030054 a(n) = binomial(2n+1,n-4). 5
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

Robert Israel, Table of n, a(n) for n = 4..1661

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

From Robert Israel, Jun 11 2019: (Start)

(54 + 36*n)*a(n) + (-438 - 129*n)*a(n + 1) + (714 + 138*n)*a(n + 2) + (-432 - 63*n)*a(n + 3) + (110 + 13*n)*a(n + 4) + (-10 - n)*a(n + 5) = 0.

a(n) ~ 2^(2*n+1)/sqrt(n*Pi). (End)

MAPLE

seq(binomial(2*n+1, n-4), n=4..50); # Robert Israel, Jun 11 2019

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 October 15 13:38 EDT 2019. Contains 328030 sequences. (Running on oeis4.)