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A309579
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Maximum principal ratio of a strongly connected digraph on n nodes.
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0
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2, 6, 22, 102, 582, 3942, 30822, 272742, 2691942, 29303142, 348637542, 4499984742, 62618845542, 934401757542, 14882928349542, 252007880413542, 4520257017565542, 85616990623453542, 1707551662741213542, 35768179777214173542, 785101998295619293542, 18019779824218937053542
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OFFSET
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3,1
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COMMENTS
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The principal ratio of a strongly connected digraph is the ratio of largest to smallest entries in the stationary distribution of a simple random walk on that digraph.
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LINKS
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FORMULA
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a(n) = (2/3) * (n-1)! * ( n/(n-1) + (1/(n-1)!) * Sum_{i=1..n-3} i! ).
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PROG
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(PARI) a(n) = (2/3) * (n-1)! * ( n/(n-1) + (1/(n-1)!) * sum(i=1, n-3, i!)); \\ Michel Marcus, Aug 11 2019
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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