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 A165628 Number of 7-regular graphs (septic graphs) on 2n vertices. 11
 1, 0, 0, 0, 1, 5, 1547, 21609301, 733351105935 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,6 COMMENTS Because the triangle A051031 is symmetric, a(n) is also the number of (2n-8)-regular graphs on 2n vertices. REFERENCES M. Meringer, Fast Generation of Regular Graphs and Construction of Cages. Journal of Graph Theory, 30 (1999), 137-146. LINKS 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 7-regular 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 Cross-references edited by the author, Nov 07 2009 and Oct 17 2011 STATUS approved

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