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A087644
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Triangle T(n,k) (n >= 2, 1 <= k <= n) read by rows: (1/2) times number of linearly inducible orderings of n points in k-dimensional Euclidean space.
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1
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1, 1, 3, 1, 6, 12, 1, 10, 36, 60, 1, 15, 86, 240, 360, 1, 21, 176, 756, 1800, 2520, 1, 28, 323, 1988, 7092, 15120, 20160, 1, 36, 547, 4572, 22996, 71856, 141120, 181440, 1, 45, 871, 9495, 64144, 278820, 787824, 1451520, 1814400, 1, 55, 1321, 18205, 159094
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OFFSET
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2,3
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COMMENTS
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Equals A071223/2. See that entry for further information.
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LINKS
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MAPLE
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T:=proc(n, k) if k>=n then 0 elif k=1 and n>=2 then 1 elif n=2 and k>=1 then 1 elif k=n-1 then n!/2 else T(n-1, k)+(n-1)*T(n-1, k-1) fi end:seq(seq(T(n, k), k=1..n-1), n=2..12);
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CROSSREFS
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KEYWORD
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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