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Graph TheoryChallengeWalks, Paths and Connectivity

Walks, Paths and Connectivity · Challenge problem

A "fan" graph has a hub vertex 00 joined to every vertex of the path 1,2,3,4,5,61,2,3,4,5,6 (edges 12,23,34,45,5612,23,34,45,56), plus the 66 spokes 01,02,03,04,05,0601,02,03,04,05,06. How many triangles does this graph contain?