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A096946
Ninth column of (1,5)-Pascal triangle A096940.
2
5, 41, 189, 645, 1815, 4455, 9867, 20163, 38610, 70070, 121550, 202878, 327522, 513570, 784890, 1172490, 1716099, 2465991, 3485075, 4851275, 6660225, 9028305, 12096045, 16031925, 21036600, 27347580, 35244396, 45054284, 57158420
OFFSET
0,1
COMMENTS
If Y is a 5-subset of an n-set X then, for n>=12, a(n-12) is the number of 8-subsets of X having at most one element in common with Y. > - Milan Janjic, Dec 08 2007
FORMULA
a(n)= (n+40)*binomial(n+7, 7)/8 = 5*b(n)-4*b(n-1), with b(n):=A000581(n+8)=binomial(n+8, 8).
G.f.: (5-4*x)/(1-x)^9.
CROSSREFS
Eighth column: A096945; tenth column: A096947.
Sequence in context: A270674 A271001 A258229 * A027954 A270623 A322420
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, Jul 16 2004
STATUS
approved