WebApr 11, 2011 · Graph, girth and expanders. In the book “ Elementary number theory, group theory and Ramanujan graphs “, Sarnak et. al. gave an elementary construction of expander graphs. We decided to go through the construction in the small seminar and I am recently assigned to give a talk about the girth estimate of such graphs. WebDec 27, 2024 · graph theory - The number of edges when girth is large - Mathematics Stack Exchange The number of edges when girth is large Ask Question Asked 3 years, 3 months ago Modified 1 year, 6 months ago Viewed 331 times 1 For any positive constant c, the girth of graph G is at least c n, where n is the number of vertices.
Contents Introduction Graphs - University of Chicago
WebMar 25, 2024 · We can bound the number of edges using the girth. Let our graph have e edges, f faces, and n vertices. Each of the graph's f faces must have at least k edges. Since each edge is contained in exactly 2 faces, we have 2 e ≥ k f. By Euler's formula, this is equivalent to 2 e ≥ k ( 2 + e − n). Some algebra gives us WebOct 1, 1983 · Corollary 3.2 shows that many types of graphs can be found in graphs of minimum degree at least 3 and large girth. For example, any graph of minimum … phone being called
inequality - Relation Between Girth and Diameter of $G
WebErdős-Gyárfás Conjecture (every graph with minimum degree 3 has a cycle whose length is a power of 2) Cages A (k,g)-cage is a graph with minimum order among all k-regular graphs with girth g. Fu-Huang-Rodger Conjecture (every (k,g)-cage is k-connected) WebNov 27, 2010 · Second, both vertices should have degree at most K − 1. When this procedure is forced to terminate for lack of such pairs, you have a graph with maximum degree K and girth at least K. Now take any vertex v of degree less than K. Look at all the vertices at distance less than K from v (including v ). This set must include all the vertices … WebProperties. As a Möbius ladder, the Wagner graph is nonplanar but has crossing number one, making it an apex graph.It can be embedded without crossings on a torus or projective plane, so it is also a toroidal graph.It has girth 4, diameter 2, radius 2, chromatic number 3, chromatic index 3 and is both 3-vertex-connected and 3-edge-connected. The Wagner … phone being monitored