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A133068 Number of surjections from an n-element set to an eight-element set. 0
40320, 1451520, 30240000, 479001600, 6411968640, 76592355840, 843184742400, 8734434508800, 86355926616960, 823172919528960, 7621934141203200, 68937160460313600, 611692004959217280, 5342844138794426880 (list; graph; refs; listen; history; text; internal format)
OFFSET

8,1

LINKS

Table of n, a(n) for n=8..21.

Index to sequences with linear recurrences with constant coefficients, signature (36,-546,4536,-22449,67284,-118124,109584,-40320).

FORMULA

a(n)=sum((-1)^(8-k)*C(8,k)*k^n) with n>=8 and k=8,7,...,1.

a(n) = A049434(n) * 8! [From Max Alekseyev, Nov 13 2009]

G.f.: 40320*x^8/((x-1)*(2*x-1)*(3*x-1)*(4*x-1)*(5*x-1)*(6*x-1)*(7*x-1)*(8*x-1)). [Colin Barker, Oct 25 2012]

CROSSREFS

Cf. A000918, A000919, A000920, A001117, A001118, A135456.

Sequence in context: A179734 A061123 A029576 * A228911 A213878 A179063

Adjacent sequences:  A133065 A133066 A133067 * A133069 A133070 A133071

KEYWORD

nonn,easy

AUTHOR

Mohamed Bouhamida (bhmd95(AT)yahoo.fr), Dec 16, 2007; Dec 21, 2007

EXTENSIONS

Edited by N. J. A. Sloane, Jul 12 2008 at the suggestion of R. J. Mathar

More terms from Max Alekseyev, Nov 13 2009

STATUS

approved

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Last modified April 16 14:51 EDT 2014. Contains 240600 sequences.