Functions > Special Functions > Other Special Functions > Gamma Functions
  
Gamma Functions
Γ(z)—Returns the value of the Euler gamma function of z.
The following relationships involving the gamma function may be useful:
Γ(z + 1) = z · Γ(z)
Γ(z)·Γ(1 − z) = π · csc(π · z)
Γ(n + 1) = n!
Γ(a, x)—Returns the value of the incomplete gamma function of x with parameter a. Γ(a, 0) = Γ(a).
lnΓ(z)—Returns the natural log of the Euler gamma function, evaluated at z.
To type Γ, press G, Ctrl+G.
Use the lnΓ function to return smaller results, then scale them.
Arguments
z is a dimensionless, real or complex scalar, undefined for z = 0, −1, −2...
For Γ(z), only arguments −107 ≤ Re(z) ≤ 171 and −106 ≤ Im(z) ≤ 106 can be evaluated without numerical overflow. For complex z, Γ(z) is the analytic continuation of the real function.
a is a dimensionless, positive, real scalar.
x is a dimensionless, positive, real scalar, or 0.