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A117665 n times the n-th n-gonal number. 0
0, 2, 6, 24, 80, 210, 462, 896, 1584, 2610, 4070, 6072, 8736, 12194, 16590, 22080, 28832, 37026, 46854, 58520, 72240, 88242, 106766, 128064, 152400, 180050, 211302, 246456, 285824, 329730, 378510, 432512, 492096, 557634, 629510, 708120, 793872 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..36.

FORMULA

a(n) = n (n + 1) (n^2 - 3 n + 4)/2. - corrected by Eric Rowland, Aug 15 2017

From Chai Wah Wu, Jul 29 2016: (Start)

a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n > 4.

G.f.: 2*x*(1 - 2*x + 7*x^2)/(1 - x)^5. (End)

CROSSREFS

Cf. A060354.

Sequence in context: A263747 A002526 A324373 * A068777 A275206 A095110

Adjacent sequences:  A117662 A117663 A117664 * A117666 A117667 A117668

KEYWORD

nonn

AUTHOR

Luc Stevens (lms022(AT)yahoo.com), Apr 11 2006

STATUS

approved

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Last modified May 25 12:30 EDT 2019. Contains 323568 sequences. (Running on oeis4.)