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A119831
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Number triangle (3n)!/(3k)!.
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1
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1, 6, 1, 720, 120, 1, 362880, 60480, 504, 1, 479001600, 79833600, 665280, 1320, 1, 1307674368000, 217945728000, 1816214400, 3603600, 2730, 1, 6402373705728000, 1067062284288000, 8892185702400, 17643225600, 13366080, 4896, 1
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OFFSET
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0,2
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COMMENTS
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LINKS
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FORMULA
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Number triangle T(n,k)=[k<=n]*(3n)!/(3k)!
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EXAMPLE
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Triangle begins
1,
6, 1,
720, 120, 1,
362880, 60480, 504, 1,
479001600, 79833600, 665280, 1320, 1,
1307674368000, 217945728000, 1816214400, 3603600, 2730, 1
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MATHEMATICA
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Flatten[Table[(3n)!/(3k)!, {n, 0, 10}, {k, 0, n}]] (* Harvey P. Dale, Jan 19 2013 *)
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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