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A181888 Second column of triangle in A182971. 3
0, 0, 9, 64, 259, 784, 1974, 4368, 8778, 16368, 28743, 48048, 77077, 119392, 179452, 262752, 375972, 527136, 725781, 983136, 1312311, 1728496, 2249170, 2894320, 3686670, 4651920, 5818995, 7220304, 8892009, 10874304, 13211704, 15953344, 19153288, 22870848, 27170913, 32124288, 37808043, 44305872, 51708462, 60113872 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

These are scaled central factorial numbers (see A182971).

LINKS

Table of n, a(n) for n=1..40.

Index entries for linear recurrences with constant coefficients, signature (7, -21, 35, -35, 21, -7, 1).

FORMULA

G.f.: x^3*(9+x)/(1-x)^7.

a(1)=0, a(2)=0, a(3)=0, a(4)=9, a(5)=64, a(6)=259, a(7)=784, a(n) = 7*a(n-1) -21*a(n-2)+35*a(n-3)-35*a(n-4)+21*a(n-5)-7*a(n-6)+a(n-7). - Harvey P. Dale, Jul 03 2013

MATHEMATICA

CoefficientList[Series[x^3(9+x)/(1-x)^7, {x, 0, 40}], x] (* or *) LinearRecurrence[ {7, -21, 35, -35, 21, -7, 1}, {0, 0, 0, 9, 64, 259, 784}, 50] (* Harvey P. Dale, Jul 03 2013 *)

CROSSREFS

Cf. A182971. Bisections give A001823 and A181889.

Sequence in context: A016886 A099761 A018201 * A000444 A143631 A083328

Adjacent sequences:  A181885 A181886 A181887 * A181889 A181890 A181891

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Feb 01 2011

STATUS

approved

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Last modified November 17 11:02 EST 2019. Contains 329226 sequences. (Running on oeis4.)