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URL: https://oeis.org/A007109

⇱ A007109 - OEIS

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A007109
Number of labeled 2-regular oriented graphs with n nodes.
1
1, 0, 0, 0, 0, 24, 570, 27900, 1827630, 152031600, 15453884376, 1884221030160, 271711899360000, 45788222207669040, 8922353083744943700, 1991728039234615305624, 505133808398958249480060
OFFSET
0,6
REFERENCES
R. W. Robinson, personal communication.
R. W. Robinson, Numerical implementation of graph counting algorithms, AGRC Grant, Math. Dept., Univ. Newcastle, Australia, 1982.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
CROSSREFS
Sequence in context: A218726 A203487 A007110 * A387372 A158538 A171329
KEYWORD
nonn
STATUS
approved