OFFSET
0,2
COMMENTS
Hales' constant used in his proof of the Kepler conjecture (Def. 1.6).
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..10000
Thomas C. Hales, A proof of the Kepler conjecture. In: Annals of Mathematics 162 (2005), nr. 3, p. 1065-1185.
FORMULA
EXAMPLE
0.0553736456...
MATHEMATICA
len = 86; PadLeft[First@ #, len + Last@ Abs@ #] &@ RealDigits@ N[4 ArcTan[Sqrt[2]/5] - Pi/3, len] (* Michael De Vlieger, Jan 09 2016 *)
RealDigits[4*ArcTan[Sqrt[2]/5] - Pi/3, 10, 100][[1]] (* G. C. Greubel, Aug 19 2018 *)
PROG
(PARI) 4*atan(sqrt(2)/5) - Pi/3 \\ G. C. Greubel, Aug 19 2018
(Magma) SetDefaultRealField(RealField(100)); R:= RealField(); 4*Arctan(Sqrt(2)/5) - Pi(R)/3; // G. C. Greubel, Aug 19 2018
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Martin Renner, Jan 09 2016
STATUS
approved