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Graph TheoryEasyEulerian and Hamiltonian Graphs

Eulerian and Hamiltonian Graphs · Easy problem

The wheel graph W5W_5 has a hub HH joined to every vertex of a 55-cycle rim 1-2-3-4-5-11\text{-}2\text{-}3\text{-}4\text{-}5\text{-}1, plus the 55 rim edges. Any Hamiltonian cycle of W5W_5 must visit HH exactly once. What is the minimum possible number of spoke edges (hub-to-rim edges) that such a Hamiltonian cycle can use?