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Revision difference : table of partial fraction expansions
Version 10 Version 9
The purpose of this entry is to collect a table of Mittag-Leffler type The purpose of this entry is to collect a table of Mittag-Leffler type
partial fraction expansions for various functions. partial fraction expansions for various functions.
\section{Elementary Functions} \section{Elementary Functions}
\begin{eqnarray} \begin{eqnarray}
\cot (\pi z) &=& {1 \over z} + \sum_{n=1}^\infty \left( {1 \over z - \cot (\pi z) &=& {1 \over z} + \sum_{n=1}^\infty \left( {1 \over z -
n} + {1 \over z + n} \right) \\ n} + {1 \over z + n} \right) \\
\pi \sec (\pi z) &=& {2 \over 1 - 2z} + \sum_{k=1}^\infty (-1)^{k+1} \pi \sec (\pi z) &=& {2 \over 1 - 2z} + \sum_{k=1}^\infty (-1)^{k+1}
\left( {2 \over 2k - 1 - 2z} - {2 \over 2k + 1 - 2z} \right) \\ \left( {2 \over 2k - 1 - 2z} - {2 \over 2k + 1 - 2z} \right) \\
\end{eqnarray} \end{eqnarray}
\section{Hypergeometric Functions} \section{Hypergeometric Functions}
\begin{eqnarray} \begin{eqnarray}
{}_2F_1 (z,1;z+1;w) &=& \sum_{k=0}^\infty {w^k \over z+k} \\ {}_2F_1 (z,1;z+1;w) &=& \sum_{k=0}^\infty {w^k \over z+k} \\
\end{eqnarray} \end{eqnarray}
\section{Gamma Functions} \section{Gamma Functions}
\begin{eqnarray} \begin{eqnarray}
{\Gamma'(z) \over Gamma(z)} &=& - \gamma + {1 \over z} + {\Gamma'(z) \over Gamma(z)} &=& - \gamma + {1 \over z} +
\sum_{k=1}^\infty \left( {1 \over n} - {1 \over z + k} \right) \\ \sum_{k=1}^\infty \left( {1 \over n} - {1 \over z + k} \right) \\
{\Gamma (x) \Gamma(\frac{1}{2}) \over \Gamma (x + \frac{1}{2})} &=& {\Gamma (x) \Gamma(\frac{1}{2}) \over \Gamma (x + \frac{1}{2})} &=&
\sum_{n=0}^\infty {(2n)! \over 2^{2n} (n!)^2} {1 \over x + n} \\ \sum_{n=0}^\infty {(2n)! \over 2^(2n) (n!)^2} {1 \over x + n} \\
\end{eqnarray} \end{eqnarray}
Here $\gamma$ is Mascheroni's constant. Here $\gamma$ is Mascheroni's constant.
\section{Elliptic Functions} \section{Elliptic Functions}
\begin{eqnarray} \begin{eqnarray}
\wp \left(z \left| \frac{1}{2} \omega, \frac{1}{2} \omega' \right.\right) &=& \wp \left(z \left| \frac{1}{2} \omega, \frac{1}{2} \omega' \right.\right) &=&
{1 \over z^2} + \sum_{|k| + |k'| \neq 0} \left( {1 \over z^2} + \sum_{|k| + |k'| \neq 0} \left(
{1 \over (z - k \omega - k' \omega')^2} - {1 \over (z - k \omega - k' \omega')^2} -
{1 \over (k \omega + k' \omega')^2} \right) \\ {1 \over (k \omega + k' \omega')^2} \right) \\
\end{eqnarray} \end{eqnarray}