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Search: id:A000256
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| A000256 |
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Number of simple triangulations of plane with n nodes. (Formerly M2923 N1173)
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+0 3
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| 1, 1, 0, 1, 3, 12, 52, 241, 1173, 5929, 30880, 164796, 897380, 4970296, 27930828, 158935761, 914325657, 5310702819, 31110146416, 183634501753, 1091371140915, 6526333259312, 39246152584304, 237214507388796, 1440503185260748
(list; graph; listen)
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OFFSET
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3,5
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REFERENCES
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W. T. Tutte, A census of planar triangulations, Canad. J. Math., 14 (1962), 21-38.
W. T. Tutte, A census of planar maps, Canad. J. Math., 15 (1963), 249-271.
W. T. Tutte, The enumerative theory of planar maps, pp. 437-448 of J. N. Srivastava, ed., A Survey of Combinatorial Theory, North-Holland, 1973.
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LINKS
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T. D. Noe, Table of n, a(n) for n=3..200
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FORMULA
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a(n) = (1/4)*(7*binomial(3*n-9, n-4)-(8*n^2-43*n+57)*a(n-1))/(8*n^2-51*n+81), n>4. - Vladeta Jovovic (vladeta(AT)Eunet.yu), Aug 19 2004
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CROSSREFS
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Adjacent sequences: A000253 A000254 A000255 this_sequence A000257 A000258 A000259
Sequence in context: A007856 A010736 A007198 this_sequence A124202 A138269 A026781
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KEYWORD
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nonn,nice
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AUTHOR
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njas
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EXTENSIONS
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More terms from Vladeta Jovovic (vladeta(AT)Eunet.yu), Aug 19 2004
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