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A096947
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Tenth column of (1,5)-Pascal triangle A096940.
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1
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5, 46, 235, 880, 2695, 7150, 17017, 37180, 75790, 145860, 267410, 470288, 797810, 1311380, 2096270, 3268760, 4984859, 7450850, 10935925, 15787200, 22447425, 31475730, 43571775, 59603700, 80640300, 107987880, 143232276, 188286560
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OFFSET
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0,1
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COMMENTS
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If Y is a 5-subset of an n-set X then, for n>=13, a(n-13) is the number of 9-subsets of X having at most one element in common with Y. - Milan Janjic, Dec 08 2007
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LINKS
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Index entries for linear recurrences with constant coefficients, signature (10,-45,120,-210,252,-210,120,-45,10,-1).
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FORMULA
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a(n) = (n+45)*binomial(n+8, 8)/9.
a(n) = 5*b(n)-4*b(n-1), with b(n) = A000582(n+9) = binomial(n+9, 9).
G.f.: (5-4*x)/(1-x)^10.
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MATHEMATICA
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CoefficientList[Series[(5-4x)/(1-x)^10, {x, 0, 40}], x] (* Harvey P. Dale, Jan 06 2020 *)
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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