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Shouldn't it be 6?

asked in Mathematical Logic by Active (2.4k points)   | 83 views
Queston Says : "The Chromatic Number of Cycle Graph with 7 vertices _____"

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no bro, for cycle graph the chromatic number can either be 2 or 3

2 in case of  even node cycle graph and 3 for odd vertex cycle graph so answer should be 3 here. just draw a cycle graph and color each vertex so that all adjacent vertex will have different color.

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https://en.wikipedia.org/wiki/Cycle_graph
chromatic no 3 if n is odd 2 if n is even

answered by Veteran (10.3k points)  
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Always remember for a Kn (complete graph) and C2n+1 (Cycle graph with odd number of vertices), chromatic number is equal to (Maximum degree +1) - BROOK'S THEOREM.

answered by Active (1.5k points)  
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if cycle graph, no.of vertices is even then chromatic no. is two because  represents minimum two colors and if no. of vertices is odd then chromatic no. is three because represents minimum three colors.

According to question no. of vertices is seven then chromatic no. is three.
answered by Active (1.3k points)  
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