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A326213
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Number of labeled n-vertex digraphs (with loops) not containing a (directed) Hamiltonian path.
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7
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OFFSET
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0,2
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COMMENTS
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A path is Hamiltonian if it passes through every vertex exactly once.
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LINKS
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FORMULA
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MATHEMATICA
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Table[Length[Select[Subsets[Tuples[Range[n], 2]], FindHamiltonianPath[Graph[Range[n], DirectedEdge@@@#]]=={}&]], {n, 0, 3}] (* Mathematica 10.2+ *)
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CROSSREFS
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Digraphs containing a Hamiltonian path are A326214.
Digraphs not containing a Hamiltonian cycle are A326220.
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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