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A054959
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Number of labeled connected Eulerian digraphs with n nodes and an odd number of edges.
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2
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0, 0, 2, 56, 3488, 664688, 434127152, 1019647579136, 8819902136934912, 284798318582888580608, 34636901578294133260750592, 15970288165992077917878979939328, 28060652850285225214988677641875677184, 188680826646319054103468721801532834939660288
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,3
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LINKS
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FORMULA
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MATHEMATICA
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A054957 = Cases[Import["https://oeis.org/A054957/b054957.txt", "Table"], {_, _}][[All, 2]];
a[n_] := (A054957[[n]] - (n - 1)!)/2;
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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