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A155856
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Triangle T(n,k)=C(2n-k,k)*(n-k)!
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6
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1, 1, 1, 2, 3, 1, 6, 10, 6, 1, 24, 42, 30, 10, 1, 120, 216, 168, 70, 15, 1, 720, 1320, 1080, 504, 140, 21, 1, 5040, 9360, 7920, 3960, 1260, 252, 28, 1, 40320, 75600, 65520, 34320, 11880, 2772, 420, 36, 1, 362880, 685440, 604800, 327600, 120120, 30888, 5544, 660
(list; table; graph; refs; listen; history; internal format)
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OFFSET
| 0,4
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COMMENTS
| Row sums are A155857. Diagonal sums are A155858.
Row sums of B^{-1}*A155856*B^{-1} are A000166 with B=A007318.
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FORMULA
| G.f.: 1/(1-xy-x/(1-xy-x/(1-xy-2x/(1-xy-2x/(1-xy-3x/(1-.... (continued fraction).
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EXAMPLE
| Triangle begins
1,
1, 1,
2, 3, 1,
6, 10, 6, 1,
24, 42, 30, 10, 1,
120, 216, 168, 70, 15, 1,
720, 1320, 1080, 504, 140, 21, 1,
5040, 9360, 7920, 3960, 1260, 252, 28, 1
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CROSSREFS
| Sequence in context: A187914 A132372 A103136 * A086960 A165675 A138771
Adjacent sequences: A155853 A155854 A155855 * A155857 A155858 A155859
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KEYWORD
| easy,nonn,tabl
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Jan 29 2009
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