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A273621
Decimal expansion of the solid angle (in steradians) subtended by a cone having the 'magic' angle A195696 as its polar angle.
1
2, 6, 5, 5, 5, 8, 6, 5, 7, 8, 7, 1, 1, 1, 5, 0, 7, 7, 5, 7, 3, 7, 1, 3, 0, 2, 5, 1, 2, 7, 4, 6, 9, 4, 3, 0, 3, 8, 2, 6, 2, 0, 6, 3, 0, 2, 5, 6, 4, 7, 3, 0, 4, 9, 0, 8, 1, 0, 1, 1, 9, 3, 1, 3, 8, 3, 9, 3, 8, 6, 4, 5, 0, 3, 1, 9, 7, 1, 0, 2, 2, 9, 8, 8, 7, 8, 1, 9, 6, 7, 4, 2, 6, 0, 1, 1, 3, 7, 9, 8, 2, 5, 1, 8, 5
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
FORMULA
Equals 2*Pi*(1-sqrt(1/3)) = 4*Pi*A156309 = 2*Pi*(1-cos(A210974)).
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