We call a bar of width on the surface of the unit sphere in -dimension, centered at the origin a spherical zone which has width and is symmetric with respect to the origin. Prove that there exists a constant such that for every positive integer the surface can be covered with bars of the same width so that every point is contained in no more than bars.
Miklós Schweitzer competition, 2015
(5 pont)
KöMaL problem A, 2015
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