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 A186725 Number of connected regular graphs with n nodes and girth at least 5. 13
 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 2, 1, 3, 1, 10, 1, 50, 1, 456, 2, 5786, 9, 91070, 3918, 1744339, 4131992, 163639193, 4018022150, 119026595851 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,11 LINKS Jason Kimberley, Connected regular graphs with girth at least 5 M. Meringer, Tables of Regular Graphs M. Meringer, Fast generation of regular graphs and construction of cages, J. Graph Theory 30 (2) (1999) 137-146. [Jason Kimberley, Jan 29 2011] FORMULA a(n) = sum of the n-th row of A186715. CROSSREFS Connected regular graphs of any degree with girth at least g: A005177 (g=3), A186724 (g=4), this sequence (g=5), A186726 (g=6), A186727 (g=7), A186728 (g=8), A186729 (g=9). Connected k-regular simple graphs with girth at least 5: this sequence (all k), A186715 (triangle); A185115 (k=2), A014372 (k=3), A058343 (k=4), A205295 (k=5). Sequence in context: A198315 A126761 A090559 * A301935 A237978 A098570 Adjacent sequences:  A186722 A186723 A186724 * A186726 A186727 A186728 KEYWORD nonn,hard,more AUTHOR Jason Kimberley, Oct 17 2011 EXTENSIONS a(26) corrected by the author, due to A186715(26,3) being corrected, May 19 2017 STATUS approved

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Last modified May 26 08:39 EDT 2020. Contains 334620 sequences. (Running on oeis4.)