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A006869
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Number of distinct vertex-degree sequences of n-faced polyhedral graphs.
(Formerly M1748)
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0
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OFFSET
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4,2
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REFERENCES
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M. B. Dillencourt, personal communication.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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Eric Weisstein's World of Mathematics, Skeleton
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EXAMPLE
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All A000944(6) = 7 topologically distinct hexahedra have distinct vertex-degree sequences, so a(6) = 7.
There are A000944(7) = 34 heptahedra (polyhedral graphs with 7 faces), but some of them have identical vertex-degree sequences. See Wikipedia for these a(7) = 18 vertex-degree sequences (or, equivalently by polyhedron duality, sets of faces). (End)
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CROSSREFS
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KEYWORD
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nonn,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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