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If a,b,c make an acute triangle, then Sqrt[(a^2 + b^2 + c^2)/8] is the radius of a sphenoid (skew tetrahedra) with those faces.
Table of n, a(n) for n=1..64.
Sequence in context: A250769 A158908 A202188 * A107977 A257226 A092457
Adjacent sequences: A060990 A060991 A060992 * A060994 A060995 A060996
Ed Pegg Jr, May 13 2001