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A326225
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Number of Hamiltonian unlabeled n-vertex digraphs (without loops).
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11
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OFFSET
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0,4
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COMMENTS
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A digraph is Hamiltonian if it contains a directed cycle passing through every vertex exactly once.
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LINKS
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EXAMPLE
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Non-isomorphic representatives of the a(3) = 4 digraph edge-sets:
{12,23,31}
{12,13,21,32}
{12,13,21,23,31}
{12,13,21,23,31,32}
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CROSSREFS
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Non-Hamiltonian unlabeled digraphs (without loops) are A326222.
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KEYWORD
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nonn,hard,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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