The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A058348 Number of connected 4-regular simple graphs on n vertices with girth at least 6. 14
 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 4, 0, 19, 0, 1272, 25, 494031, 13504 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,31 COMMENTS From Jason Kimberley, 2011: (Start) The null graph on 0 vertices is vacuously connected and 4-regular; since it is acyclic, it has infinite girth. Does a(2n+1) ever exceed a(2n)? (End) LINKS Table of n, a(n) for n=0..37. Jason Kimberley, Connected regular graphs with girth at least 6 Jason Kimberley, Index of sequences counting connected k-regular simple graphs with girth at least g 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] CROSSREFS From Jason Kimberley, Jan 29 2011: (Start) Connected k-regular simple graphs with girth at least 6: A186726 (any k), A186716 (triangle); specified degree k: A185116 (k=2), A014374 (k=3), this sequence (k=4). Connected 4-regular simple graphs with girth at least g: A006820 (g=3), A033886 (g=4), A058343 (g=5), this sequence (g=6). Connected 4-regular simple graphs with girth exactly g: A184943 (g=3), A184944 (g=4), A184945 (g=5). (End) Sequence in context: A244310 A334705 A156457 * A184946 A351615 A362058 Adjacent sequences: A058345 A058346 A058347 * A058349 A058350 A058351 KEYWORD nonn,more,hard AUTHOR N. J. A. Sloane, Dec 17 2000 EXTENSIONS Jason Kimberley inserted Meringer's computed terms a(n)=0 for n in [27,29,31,33] and appended terms a(35) and a(36), by running Meringer's GENREG for 17 and 106 processor days at U. Ncle, on May 04 2010. a(37) appended from running GENREG for 450 processor days at U. Ncle. by Jason Kimberley, Dec 03 2011 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified February 21 10:54 EST 2024. Contains 370233 sequences. (Running on oeis4.)