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A155122 a(n) = 4*(3*n+2)*(2*n+1)*(n+2)*(n+1). 2
0, 16, 360, 1920, 6160, 15120, 31416, 58240, 99360, 159120, 242440, 354816, 502320, 691600, 929880, 1224960, 1585216, 2019600, 2537640, 3149440, 3865680, 4697616, 5657080, 6756480, 8008800, 9427600, 11027016, 12821760, 14827120, 17058960 (list; graph; refs; listen; history; text; internal format)
OFFSET

-1,2

COMMENTS

Middle function 5th down in the triangle A155120.

LINKS

G. C. Greubel, Table of n, a(n) for n = -1..1000

Index entries for linear recurrences with constant coefficients, signature (5,-10,10,-5,1).

FORMULA

a(n) = 16 + 80*n + 140*n^2 + 100*n^3 + 24*n^4.

G.f.: 8*(2 +35*x +35*x^2)/(1-x)^5.

E.g.f.: 4*(4 + 86*x + 152*x^2 + 61*x^3 + 6*x^4)*exp(x). - G. C. Greubel, Mar 25 2021

MAPLE

seq( 4*(3*n+2)*(2*n+1)*(n+2)*(n+1), n=-1..30); # G. C. Greubel, Mar 25 2021

MATHEMATICA

Table[16 +80*n +140*n^2 +100*n^3 +24*n^4, {n, -1, 30}]

PROG

(Magma) [4*(3*n+2)*(2*n+1)*(n+2)*(n+1): n in [-1..30]]; // G. C. Greubel, Mar 25 2021

(Sage) [4*(3*n+2)*(2*n+1)*(n+2)*(n+1) for n in (-1..30)] # G. C. Greubel, Mar 25 2021

CROSSREFS

Cf. A142463.

Sequence in context: A171680 A208706 A278622 * A094101 A034673 A000488

Adjacent sequences:  A155119 A155120 A155121 * A155123 A155124 A155125

KEYWORD

nonn,easy

AUTHOR

Roger L. Bagula, Jan 20 2009

EXTENSIONS

Edited by the Associate Editors of the OEIS, Nov 08 2009, Dec 15 2010

STATUS

approved

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Last modified October 3 22:17 EDT 2022. Contains 357237 sequences. (Running on oeis4.)