info prev up next book cdrom email home

Hutton's Formula

The Machin-Like Formula

\begin{displaymath}
{\textstyle{1\over 4}}\pi=2\tan^{-1}({\textstyle{1\over 3}})+\tan^{-1}({\textstyle{1\over 7}}).
\end{displaymath}

The other two-term Machin-Like Formulas are Euler's Machin-Like Formula, Hermann's Formula, and Machin's Formula.




© 1996-9 Eric W. Weisstein
1999-05-25