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A159623
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Triangle read by rows: T(n,m) = if m<=floor(n/2) then n!/(n - m)! otherwise n!/m!
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3
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1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 4, 12, 4, 1, 1, 5, 20, 20, 5, 1, 1, 6, 30, 120, 30, 6, 1, 1, 7, 42, 210, 210, 42, 7, 1, 1, 8, 56, 336, 1680, 336, 56, 8, 1, 1, 9, 72, 504, 3024, 3024, 504, 72, 9, 1, 1, 10, 90, 720, 5040, 30240, 5040, 720, 90, 10, 1
(list;
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refs;
listen;
history;
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OFFSET
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0,5
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COMMENTS
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The row sums are: {1, 2, 4, 8, 22, 52, 194, 520, 2482, 7220, 41962,...}.
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LINKS
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Table of n, a(n) for n=0..65.
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EXAMPLE
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{1},
{1, 1},
{1, 2, 1},
{1, 3, 3, 1},
{1, 4, 12, 4, 1},
{1, 5, 20, 20, 5, 1},
{1, 6, 30, 120, 30, 6, 1},
{1, 7, 42, 210, 210, 42, 7, 1},
{1, 8, 56, 336, 1680, 336, 56, 8, 1},
{1, 9, 72, 504, 3024, 3024, 504, 72, 9, 1},
{1, 10, 90, 720, 5040, 30240, 5040, 720, 90, 10, 1}
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MATHEMATICA
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Clear[t, n, m];
t[n_, m_] = If[m <= Floor[n/2], n!/(n - m)!, n!/m! ];
Table[t[n, m], {n, 0, 10}, {m, 0, n}];
Flatten[%]
Table[Sum[t[n, m], {m, 0, n}], {n, 0, 10}];
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CROSSREFS
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Sequence in context: A123610 A209631 A059922 * A143199 A137896 A157219
Adjacent sequences: A159620 A159621 A159622 * A159624 A159625 A159626
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KEYWORD
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nonn,tabl
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AUTHOR
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Roger L. Bagula, Apr 17 2009
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EXTENSIONS
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Edited by N. J. A. Sloane, Apr 17 2009
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STATUS
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approved
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