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4. Proper graph colorings Recall that a proper coloring of a graph is one where colors are given t ...
4. Proper graph colorings Recall that a proper coloring of a graph is one where colors are given to each vertex such that every pair of adjacent vertices have different colors. Shown below are the graphs K, (the complete graph on 5 vertices), C (the cycle graph on 5 vertices), and the Petersen graph. For each, determine the fewest colors one needs to properly color each and explain why fewer colors won't work. K? C5 Petersen graph
The first graph K5 is a complete graph. That is all the vertices adjacent.so we cannot use a single colour to properly colour all the vertices, since adjacen