

A165628


Number of 7regular graphs (septic graphs) on 2n vertices.


11




OFFSET

0,6


COMMENTS

Because the triangle A051031 is symmetric, a(n) is also the number of (2n8)regular graphs on 2n vertices.


REFERENCES

M. Meringer, Fast Generation of Regular Graphs and Construction of Cages. Journal of Graph Theory, 30 (1999), 137146.


LINKS

Table of n, a(n) for n=0..8.
Jason Kimberley, Index of sequences counting not necessarily connected kregular simple graphs with girth at least g
M. Meringer, Tables of Regular Graphs
N. J. A. Sloane, Transforms
Eric Weisstein's World of Mathematics, Septic Graph


FORMULA

Euler transformation of A014377.


CROSSREFS

7regular simple graphs: A014377 (connected), A165877 (disconnected), this sequence (not necessarily connected).
Regular graphs A005176 (any degree), A051031 (triangular array), chosen degrees: A000012 (k=0), A059841 (k=1), A008483 (k=2), A005638 (k=3), A033301 (k=4), A165626 (k=5), A165627 (k=6), this sequence (k=7), A180260 (k=8).
Sequence in context: A184973 A184971 A014377 * A119747 A177906 A127106
Adjacent sequences: A165625 A165626 A165627 * A165629 A165630 A165631


KEYWORD

nonn,hard,more,changed


AUTHOR

Jason Kimberley, Sep 22 2009


EXTENSIONS

Crossreferences edited by the author, Nov 07 2009 and Oct 17 2011


STATUS

approved



