OFFSET
0,1
COMMENTS
Also the vertex solid angle of a regular tetrahedron.
LINKS
Stanislav Sykora, Table of n, a(n) for n = 0..2000
Eric Weisstein's World of Mathematics, Cuboctahedron
Eric Weisstein's World of Mathematics, Spherical Polygon
Wikipedia, Platonic solid
FORMULA
arccos(23/27).
3*arcsin(2*sqrt(2)/3) - Pi. - Bradley Klee, Oct 04 2018
EXAMPLE
0.55128559843253080794214415146445924293385062869017869619170040868416...
MATHEMATICA
RealDigits[N[ArcCos[23/27], 107]][[1]] (* T. D. Noe, Jan 29 2014 *)
CROSSREFS
KEYWORD
AUTHOR
Stanislav Sykora, Jan 28 2014
EXTENSIONS
Definition corrected by Bradley Klee, Oct 04 2018
STATUS
approved