OFFSET
2,1
COMMENTS
Also known as "magic angle", the angle t such that 3*(cos t)^2 - 1 = 0.
See more comments in A195696. - Stanislav Sykora, Nov 14 2013
LINKS
C. O. Horgan and J. G. Murphy, On an angle with magical properties, Notices Amer. Math. Soc., 69:1 (2022), 22-25.
Wikipedia, Tetrahedron
Wikipedia, Magic angle
EXAMPLE
54.7356103172453... degrees.
MATHEMATICA
RealDigits[t/.FindRoot[3Cos[t Degree]^2-1==0, {t, 54}, WorkingPrecision-> 120]][[1]] (* Harvey P. Dale, May 02 2014 *)
PROG
(PARI) acos(sqrt(1/3))*180/Pi \\ Charles R Greathouse IV, Nov 05 2017
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Omar E. Pol, Jul 17 2012
STATUS
approved