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Blockers for simple Hamiltonian paths in convex geometric graphs of even order

Let G be a complete convex geometric graph on 2m vertices, and let F be a family of subgraphs of G. A blocker for F is a set of edges, of smallest possible size, that meets every element of F. In [C. Keller and M. A. Perles, On the smallest sets blocking simple perfect matchings in a convex geometric graph, Israel J. Math. 187 (2012), pp. 465-484], we gave an explicit description of all blockers for the family of simple perfect matchings (SPMs) of G. In this paper we show that the family of simple Hamiltonian paths (SHPs) in G has exactly the same blockers as the family of SPMs. Our argument is rather short, and provides a much simpler proof of the result of [KP12].