Digamma

From specialfunctionswiki
Revision as of 06:54, 21 December 2016 by Tom (talk | contribs)
Jump to: navigation, search

The digamma function $\psi \colon \mathbb{C} \setminus \{0,-1,-2,\ldots\} \rightarrow \mathbb{C}$ is defined by $$\psi(z) = \dfrac{\mathrm{d}}{\mathrm{d}z} \log \Gamma(z) = \dfrac{\Gamma'(z)}{\Gamma(z)}.$$

Properties

Partial derivative of beta function
Digamma at 1
Digamma functional equation
Digamma at n+1

See Also

Gamma
Polygamma
Trigamma

References