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 A054959 Number of labeled connected Eulerian digraphs with n nodes and an odd number of edges. 2
 0, 0, 2, 56, 3488, 664688, 434127152, 1019647579136, 8819902136934912, 284798318582888580608, 34636901578294133260750592, 15970288165992077917878979939328, 28060652850285225214988677641875677184, 188680826646319054103468721801532834939660288 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Table of n, a(n) for n=1..14. V. A. Liskovets, Some easily derivable sequences, J. Integer Sequences, 3 (2000), #00.2.2. FORMULA a(n) = (A054957(n) - (n-1)!)/2. - Andrew Howroyd, Sep 10 2018 MATHEMATICA A054957 = Cases[Import["https://oeis.org/A054957/b054957.txt", "Table"], {_, _}][[All, 2]]; a[n_] := (A054957[[n]] - (n - 1)!)/2; Array[a, 14] (* Jean-François Alcover, Sep 13 2019 *) CROSSREFS Cf. A058338, A054955, A007080, A054956, A058337, A054958, A054957. Sequence in context: A193475 A246001 A009555 * A206305 A325291 A326551 Adjacent sequences: A054956 A054957 A054958 * A054960 A054961 A054962 KEYWORD nonn,easy AUTHOR N. J. A. Sloane, May 24 2000 EXTENSIONS More terms from Vladeta Jovovic, Mar 06 2001 a(12)-a(14) from Andrew Howroyd, Sep 10 2018 STATUS approved

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Last modified August 7 17:21 EDT 2024. Contains 375017 sequences. (Running on oeis4.)