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Search: id:A058786
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| A058786 |
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Number of n-hedra with 2n-5 vertices or 3n-7 edges (the vertices of these are all of degree 3, except one which is of degree 4). Alternatively, the number of polyhedra with n vertices whose faces are all triangular, except one which is tetragonal. |
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4
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| 1, 2, 8, 38, 219, 1404, 9714, 70454, 527235, 4037671, 31477887, 249026400, 1994599707, 16147744792
(list; graph; listen)
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OFFSET
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5,2
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LINKS
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G. P. Michon, Counting Polyhedra
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EXAMPLE
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a(5)=1 because the square pyramid is the only pentahedron with 5=2*5-5 vertices (or 8=3*5-7 edges). Alternatively, a(5)=1 because the square pyramid is the only polyhedron with 5 vertices whose faces are all triangles with only one tetragonal exception.
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CROSSREFS
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Cf. A000109, A002856, A000944, A002840, A058787, A058788, A049337.
Sequence in context: A108246 A020031 A001340 this_sequence A096654 A060389 A101714
Adjacent sequences: A058783 A058784 A058785 this_sequence A058787 A058788 A058789
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KEYWORD
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hard,nonn,nice
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AUTHOR
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Gerard P. Michon (g.michon(AT)att.net), Nov 29 2000
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