classify strongly regular graph with parameter (25,12,5,6) - MathOverflow most recent 30 from http://mathoverflow.net 2013-05-24T18:44:13Z http://mathoverflow.net/feeds/question/97776 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/97776/classify-strongly-regular-graph-with-parameter-25-12-5-6 classify strongly regular graph with parameter (25,12,5,6) mj125 2012-05-23T17:25:22Z 2012-05-23T18:16:27Z <p>how can i classify strongly regular graph with parameter $(25,12,5,6)$?</p> <p>just i know we have fifteen $SRG(25,12,5,6)$ that two come from latin square(5)</p> http://mathoverflow.net/questions/97776/classify-strongly-regular-graph-with-parameter-25-12-5-6/97780#97780 Answer by Zack Wolske for classify strongly regular graph with parameter (25,12,5,6) Zack Wolske 2012-05-23T18:16:27Z 2012-05-23T18:16:27Z <p>What you're really looking for are conference graphs of order 25, which come from <a href="http://en.wikipedia.org/wiki/Conference_matrix" rel="nofollow">symmetric conference matrices</a> of order 26. Your 15 known graphs are the Paulus graphs on 26 nodes, and the 10 are Paulus graphs on 26 nodes. That should be enough to find the answers you want in the literature.</p>