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A156367
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Number triangle T(n,k)=C(n+k,2k)*k!
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1
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1, 1, 1, 1, 3, 2, 1, 6, 10, 6, 1, 10, 30, 42, 24, 1, 15, 70, 168, 216, 120, 1, 21, 140, 504, 1080, 1320, 720, 1, 28, 252, 1260, 3960, 7920, 9360, 5040, 1, 36, 420, 2772, 11880, 34320, 65520, 75600, 40320, 1, 45, 660, 5544, 30888, 120120, 327600, 604800
(list; table; graph; refs; listen; history; internal format)
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OFFSET
| 0,5
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COMMENTS
| Row sums are A155857. Diagonal sums are A084261. Reversal of A155856.
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FORMULA
| G.f.: 1/(1-x-xy/(1-x-xy/(1-x-2xy/(1-x-2xy/(1-x-3xy/(1-x-3xy/(1-... (continued fraction).
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EXAMPLE
| Triangle begins
1,
1, 1,
1, 3, 2,
1, 6, 10, 6,
1, 10, 30, 42, 24,
1, 15, 70, 168, 216, 120,
1, 21, 140, 504, 1080, 1320, 720,
1, 28, 252, 1260, 3960, 7920, 9360, 5040,
1, 36, 420, 2772, 11880, 34320, 65520, 75600, 40320
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CROSSREFS
| Sequence in context: A088617 A190909 A144250 * A193593 A181853 A008276
Adjacent sequences: A156364 A156365 A156366 * A156368 A156369 A156370
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KEYWORD
| easy,nonn,tabl
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Feb 08 2009
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