A048179 Number of graphs with n nodes and n+1 edges.

1, 6, 24, 97, 402, 1637, 6759, 28259, 119890, 517121, 2271860, 10176660, 46541024, 217511951, 1039651295, 5084972068, 25458149446, 130480742790, 684550272269, 3675258986639, 20184618368312, 113340974676578, 650343587802644

Offset

4,2

References

J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 146.

Links

Andrew Howroyd, Table of n, a(n) for n = 4..50 (terms 4..37 from Sean A. Irvine)

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.

Formula

a(n) = A008406(n, n+1). - Andrew Howroyd, Jan 09 2024

Prog

(PARI) a(n) = polcoef(G(n, O(x^(n+2))), n+1) \\ G defined in A008406. - Andrew Howroyd, Jan 09 2024

Crossrefs

Cf. A008406.

Sequence in context: A164908 A290911 A037505 * A117614 A037688 A343116

Adjacent sequences: A048176 A048177 A048178 * A048180 A048181 A048182

Keyword

nonn,easy,nice

Author

N. J. A. Sloane

Extensions

More terms from Vladeta Jovovic, Jan 07 2000

More terms from Sean A. Irvine, Jun 06 2017

Status

approved