Definition


The gamma function is a special function defined for all complex numbers except non-positive numbers. It is also known as the The Euler integral of the second kind. It is denoted by the uppercase Greek letter “Gamma” :

The gamma function is defined by Analytic Continuation. It is a Meromorphic function with no zeros and with simple poles of residue for every positive integers . is an Entire Function with simple zeros at .

For every positive integers the gamma function is Factorial of :

Functional Relations


  • Recurrence:
  • Euler’s reflection formula:
  • Legendre duplication formula:
  • Gauss’s multiplication formula:

Other Properties


  • Complex conjugate:
  • Absolute value:
  • Derivative: