A001432 Number of graphs with n nodes and n-4 edges.

0, 0, 0, 1, 1, 2, 5, 11, 25, 66, 172, 485, 1446, 4541, 15036, 52496, 192218, 737248, 2952621, 12313532, 53336122, 239380403, 1110793092, 5318743428, 26233496486, 133074975399

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• easy

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

• Sean A. Irvine, Table of n, a(n) for n = 1..40
• 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.

Crossrefs

Cf. A008406.

Programs

Mathematica

(* first do *) Needs["Combinatorica`"] (* then *) Table[ NumberOfGraphs[n, n-4], {n, 4, 26}] (* Robert G. Wilson v *)

Extensions

More terms from Vladeta Jovovic, Jan 03 2000