On Sunday, October 9, 2016 at 9:10:50 PM UTC, ni732...@gmail.com wrote: > > Brown's construction is the function which takes a finite field to a graph > with diameter 2. > http://www.emis.ams.org/journals/EJC/Surveys/ds14.pdf > > Is it available in the graph component of sagemath? >
I won't be surprised if it could be constructed as a subgraph of one of many strongly regular graphs known to Sage, but there is no direct way to build such a graph in Sage, IMHO. The description of the adjacency in the link you provide is a bit too brief to see what exactly it does, but I think these graphs are also known as Erdős–Rényi graphs, from P. Erdós, A. Rényi, V.T. Sós On a problem of graph theory Studia Sci. Math. Hungar., 1 (1966), pp. 215–235 Brown's paper was published in the same year: W.G. Brown On graphs that do not contain a Thomsen graph Canad. Math. Bull., 9 (1966), pp. 281–285 We published a paper where these graphs were considered, and I implemented a construction of them in GAP, but not in Sage :-) https://www.cs.ox.ac.uk/publications/publication7266-abstract.html Please feel free to cc me on the Sage ticket with an implementation, I'd be glad to review it. Dima > If not, I plan to implement it for sagemath. > > yawara > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.