Graphs With Large Girth And Large Chromatic Number
نویسنده
چکیده
In the first part of these notes we use a probabilistic method to show the existence of graphs with large girth and large chromatic number. In the second part we give an explicit example of such graphs. It is mostly based on the third chapter of Some Applications Of Modular Forms by Peter Sarnak and also the third and forth chapters of Elementary Number Theory, Group Theory, And Ramanujan Graphs by Giuliana Davidoff, Peter Sarnak and Alain Valette.
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