Abstract
An n-simplex is called circumscriptible (or edge-incentric) if there is a sphere which is tangent to all its n(n + 1)/2 edges. We obtain a closed formula for the radius of the circumscribed sphere of a circumscriptible n-simplex, and we prove a double inequality involving the circumradius and the edge-inradius of such simplices. With these results a part of a problem posed by the authors is solved.
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Dedicated to Professor Lu Yang
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Wu, YD., Zhang, ZH. On the Circumradius of a Special Class of n-Simplices. Results. Math. 61, 29–42 (2012). https://doi.org/10.1007/s00025-010-0073-x
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DOI: https://doi.org/10.1007/s00025-010-0073-x