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A090448 Fourth column (m=3) of triangle A090447. 5
9, 96, 500, 1800, 5145, 12544, 27216, 54000, 99825, 174240, 290004, 463736, 716625, 1075200, 1572160, 2247264, 3148281, 4332000, 5865300, 7826280, 10305449, 13406976, 17250000, 21970000, 27720225, 34673184, 43022196, 52983000 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,1

LINKS

Table of n, a(n) for n=3..30.

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

FORMULA

a(n) = A090447(n,3).

a(n) = (n^3*(n-1)^2*(n-2)^1)/(1!*2!*3!) for n >= 3.

From Colin Barker, Jan 21 2013: (Start)

a(n) = (n^6-4*n^5+5*n^4-2*n^3)/12.

G.f.: -x^3*(x^3+17*x^2+33*x+9)/(x-1)^7. (End)

a(n) = A000330(n-1)^2 - A000292(n-1)^2. - J. M. Bergot, May 02 2014

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). - Wesley Ivan Hurt, May 04 2021

MAPLE

seq(mul(binomial(n, k), k=1..3), n=3..30); # Zerinvary Lajos, Dec 13 2007

CROSSREFS

Cf. A000292, A000330, A090447.

Sequence in context: A052389 A197665 A064504 * A264219 A005545 A228007

Adjacent sequences:  A090445 A090446 A090447 * A090449 A090450 A090451

KEYWORD

nonn,easy,changed

AUTHOR

Wolfdieter Lang, Dec 23 2003

STATUS

approved

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Last modified May 12 10:54 EDT 2021. Contains 343821 sequences. (Running on oeis4.)