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A001431
Number of graphs with n nodes and n-3 edges.
(Formerly M1382 N0540)
2
0, 0, 1, 1, 2, 5, 10, 24, 63, 165, 467, 1405, 4435, 14775, 51814, 190443, 732472, 2939612, 12277230, 53233295, 239083372, 1109921554, 5316143531, 26225625392, 133050795412, 693227353094, 3704785464812, 20285853687809, 113690627637475, 651559904414667
OFFSET
1,5
REFERENCES
J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 146.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
M. L. Stein and P. R. Stein, Enumeration of Linear Graphs and Connected Linear Graphs up to p = 18 Points. Report LA-3775, Los Alamos Scientific Laboratory of the University of California, Los Alamos, NM, Oct 1967.
MATHEMATICA
(* first do *) Needs["Combinatorica`"] (* then *) Table[ NumberOfGraphs[n, n-3], {n, 3, 27}] (* Robert G. Wilson v *)
CROSSREFS
Cf. A008406.
Sequence in context: A321007 A253013 A192471 * A324149 A054866 A242935
KEYWORD
nonn,easy
EXTENSIONS
More terms from Vladeta Jovovic, Jan 12 2000
STATUS
approved