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A051790
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a(n) = C(n)*(C(n)-1)*(C(n)-2)/6, where C(n) are the Catalan numbers (A000108).
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1
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0, 0, 0, 10, 364, 11480, 374660, 13067054, 486345860, 19143687420, 789566607180, 33856987804640, 1500056631216220, 68334193148209300, 3188209413930298680, 151869731557849844790, 7367151946247774981940, 363173327612427801849380
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OFFSET
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0,4
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LINKS
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FORMULA
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MAPLE
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[seq (binomial(binomial(2*n, n)/(n+1), 3), n=0..24)]; # Zerinvary Lajos, May 29 2006
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MATHEMATICA
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(#(#-1)(#-2))/6&/@CatalanNumber[Range[0, 20]] (* Harvey P. Dale, Oct 12 2014 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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