Eufisky - The lost book

FoxTrot Series

在这里,介绍了FoxTrot Series.

\[F = \sum\limits_{n = 1}^\infty {\frac{{{{\left( { - 1} \right)}^{n + 1}}{n^2}}}{{{n^3} + 1}}} = \frac{1}{3}\left[ {1 - \ln 2 + \pi \mathrm{sech}\left( {\frac{{\sqrt 3 }}{2}\pi } \right)} \right].\]

另外,在这里有一些极限讨论