4 ms·

See also Emil Artin's elegant pamphlet, "The Gamma Function".

• rspeer 12y ago
  It's awesome and weird that there's a consistent and useful function that lets you define an equivalent to (-1/2)! -- and that what you get is the square root of pi.
  • SamReidHughes 12y ago
    Of course it has pi in it. Otherwise it'd have to have e in it.
  • mturmon 12y ago
    I agree. The Stirling formula is another place where the square root of pi pops out from factorials.