Geodesic
An N-Parameter Chebyshev Set which is not a Sun
Canadian mathematical bulletin, Tome 18 (1975) no. 4, pp. 489-492

Voir la notice de l'article provenant de la source Cambridge University Press

Recently, Dunham has given examples for 1-parameter and 2-parameter Chebyshev sets which are not suns. In this note 2-parameter sets with these properties are described.When studying the old problem whether Chebyshev sets are always convex, Klee [10] introduced certain sets which were called suns by Efimov and Stechkin [7]. Recently, in two shorts notes Dunham [4, 5] has given examples of 1-parameter- and 2-parameter-sets which are Chebyshev sets but not suns (cf. also [3]). The examples refer to Chebyshev sets in containing an isolated point.
DOI : 10.4153/CMB-1975-089-5
Mots-clés : Convexity of Chebyshev sets, 41 A 65, 41 A 50 
Braess, Dietrich. An N-Parameter Chebyshev Set which is not a Sun. Canadian mathematical bulletin, Tome 18 (1975) no. 4, pp. 489-492. doi: 10.4153/CMB-1975-089-5
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