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A095664 Ninth column (m=8) of (1,3)-Pascal triangle A095660. 3
3, 25, 117, 405, 1155, 2871, 6435, 13299, 25740, 47190, 82654, 139230, 226746, 358530, 552330, 831402, 1225785, 1773783, 2523675, 3535675, 4884165, 6660225, 8974485, 11960325, 15777450, 20615868, 26700300, 34295052, 43709380, 55303380, 69494436, 86764260, 107666559, 132835365, 162994065 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

If Y is a 3-subset of an n-set X then, for n>=10, a(n-10) is the number of 8-subsets of X having at most one element in common with Y. - Milan Janjic, Nov 23 2007

LINKS

Table of n, a(n) for n=0..34.

FORMULA

a(n)= binomial(n+7, 7)*(n+24)/8 = 3*b(n)-2*b(n-1), with b(n):=binomial(n+8, 8); cf. A000581.

G.f.: (3-2*x)/(1-x)^9.

PROG

(PARI) x='x+O('x^66); Vec((3-2*x)/(1-x)^9) \\ Joerg Arndt, May 11 2013

CROSSREFS

Eighth column: A095663. Tenth column: A095665.

Sequence in context: A201534 A059457 A165206 * A215773 A099868 A243228

Adjacent sequences:  A095661 A095662 A095663 * A095665 A095666 A095667

KEYWORD

nonn,easy

AUTHOR

Wolfdieter Lang, Jun 11 2004

STATUS

approved

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Last modified May 9 04:58 EDT 2021. Contains 343687 sequences. (Running on oeis4.)