Robbin Constant

$\begin{displaymath} R={\textstyle{4\over 105}}+{\textstyle{17\over 105}}\sqrt{2}... ...ln(2+\sqrt{3}\,)-{\textstyle{1\over 15}}\pi=0.661707182\ldots. \end{displaymath}$

See also Transfinite Diameter

References

Plouffe, S. ``The Robbin Constant.'' http://www.lacim.uqam.ca/piDATA/robbin.txt.