Category:Trigamma Function

This category contains results about Trigamma Function.

The trigamma function, $\psi_1$, is defined, for $z \in \C \setminus \Z_{\le 0}$, to be the $1$st derivative of the digamma function:

$\map {\psi_1} z = \dfrac {\d} {\d z} \map \psi z$

where $\psi$ is the digamma function.