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A317487
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Number of 4-cycles in the n-Bruhat graph.
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2
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0, 0, 0, 6, 90, 1080, 12600, 151200, 1905120, 25401600, 359251200, 5388768000, 85621536000, 1438441804800, 25499650176000, 475993469952000, 9336794987520000, 192071211171840000, 4135933413900288000, 93058501812756480000, 2184137777840578560000, 53390034569436364800000
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OFFSET
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1,4
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LINKS
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FORMULA
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PROG
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(PARI) a(n) = if(n > 1, n!*(n-2)*(n-3)/8, 0); \\ Andrew Howroyd, Jul 30 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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