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A100960
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Triangle read by rows: T(n,k) = number of labeled 2-connected planar graphs with n nodes and k edges, n >= 3, n <= k <= 3(k-2).
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1
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1, 3, 6, 1, 12, 70, 100, 45, 10, 60, 720, 2445, 3525, 2637, 1125, 195
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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3,2
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REFERENCES
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E. A. Bender, Z. Gao and N. C. Wormald, The number of labeled 2-connected planar graphs, Electron. J. Combin., 9 (2002), #R43.
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LINKS
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Table of n, a(n) for n=3..18.
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EXAMPLE
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The triangle T(n,k), n>=3, k>=3 begins:
1
0 3 6 1
0 0 12 70 100 45 10
0 0 0 60 720 2445 3525 2637 1125 195
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CROSSREFS
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Row sums give A096331. Main diagonal is A001170.
Sequence in context: A120229 A192100 A123534 * A130852 A138799 A108441
Adjacent sequences: A100957 A100958 A100959 * A100961 A100962 A100963
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KEYWORD
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nonn,tabf,more
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AUTHOR
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N. J. A. Sloane, Jan 12 2005
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EXTENSIONS
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The Bender et al. paper (on the web) gives many more terms.
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STATUS
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approved
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