

A186727


Number of connected regular graphs with n nodes and girth at least 7.


12



1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 4, 1, 22, 1, 547, 1, 30369, 1, 1782841, 1, 95079084, 1, 4686063121, 1
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OFFSET

0,25


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..39.
Jason Kimberley, Index of sequences counting connected kregular simple graphs with girth at least g
Jason Kimberley, Connected regular graphs with girth at least 7
M. Meringer, Tables of Regular Graphs


FORMULA

a(n) = sum of the nth row of A186717.


CROSSREFS

Connected regular graphs of any degree with girth at least g: A005177 (g=3), A186724 (g=4), A186725 (g=5), A186726 (g=6), this sequence (g=7), A186728 (g=8), A186729 (g=9).
Connected kregular simple graphs with girth at least 7: this sequence (any k), A186717 (triangle); specific k: A185117 (k=2), A014375 (k=3).
Sequence in context: A092891 A229484 A080212 * A145998 A218952 A177413
Adjacent sequences: A186724 A186725 A186726 * A186728 A186729 A186730


KEYWORD

nonn,more,hard


AUTHOR

Jason Kimberley, Nov 25 2011


STATUS

approved



