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A095819
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Tenth column (m=9) of (1,4)-Pascal triangle A095666.
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1
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4, 37, 190, 715, 2200, 5863, 14014, 30745, 62920, 121550, 223652, 394706, 671840, 1107890, 1776500, 2778446, 4249388, 6369275, 9373650, 13567125, 19339320, 27183585, 37718850, 51714975, 70122000, 94103724, 125076072, 164750740
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OFFSET
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0,1
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COMMENTS
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If Y is a 4-subset of an n-set X then, for n>=12, a(n-12) 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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FORMULA
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G.f.: (4-3*x)/(1-x)^10.
a(n) = 4*b(n)-3*b(n-1) =(n+36)*binomial(n+8, 8)/9, with b(n):=binomial(n+9, 9)=A000582(n+9, 9).
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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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