OFFSET
1,1
COMMENTS
An example of such a cone is the one circumscribed to a cube from one of its vertices. When expressed as a fraction of the full solid angle, this constant leads to A156309.
LINKS
Stanislav Sykora, Table of n, a(n) for n = 1..2000
EXAMPLE
2.65558657871115077573713025127469430382620630256473049081011931...
MATHEMATICA
First@RealDigits@N[2*Pi*(1 - Sqrt[1/3]), 25] (* G. C. Greubel, Aug 15 2016 *)
PROG
(PARI) 2*Pi*(1-sqrt(1/3))
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Stanislav Sykora, Aug 15 2016
STATUS
approved