F. A. Valentine in [4] proved the following two theorems.THEOREM 1. Let S be a closed connected subset of Rd which has at most n points of local nonconvexity. Then S is an Ln+i set.THEOREM 2. Let S be a closed connected subset of Rd whose points of local nonconvexity are decomposable into n closed convex sets. Then S is an L2n+i set.These results have been extended by a number of authors, but always with stronger hypothesis. (See [1] and [2].) Using a minimal arc technique, new pr∞fs of Theorems 1 and 2 were given in [3].Valentine remarks in [4] that Theorem 2 might be improved in the case that 5 is the closure of an open connected set. The goal of this paper is to give such an improvement for sets satisfying a particular local connectivity property.
Stavrakas, Nick M. Ln Sets and the Closures of Open Connected Sets. Canadian journal of mathematics, Tome 27 (1975) no. 1, pp. 1-5. doi: 10.4153/CJM-1975-001-3
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author = {Stavrakas, Nick M.},
title = {Ln {Sets} and the {Closures} of {Open} {Connected} {Sets}},
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year = {1975},
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