Polygamma function
type: Concept
preferred label: تابع چند گاما @fa
related: trigamma function

digamma function
type: Concept
preferred label: تابع دایگاما @fa
related: trigamma function

trigamma function
type: Concept
broader: gamma function
preferred label: تابع سه گاما @fa
related: Polygamma function
related: digamma function

gamma function
type: Concept
narrower: trigamma function
preferred label: تابع گاما @fa