Azeppo.107 net.general utcsrgv!utzoo!decvax!ucbvax!mhtsa!harpo!zeppo!raj Mon Jan 25 09:48:09 1982 Factorial Query Concerning the question why 0! is defined to be 1, there is another reason. Anyone who has taken probability theory has learned that the formula which gives the number of combinations of n objects taken k at a time is n!/k!(n-k)! For the case when k=n, the formula should give the result 1, which makes it necessary for 0! to be 1. zeppo!raj ----------------------------------------------------------------- gopher://quux.org/ conversion by John Goerzen of http://communication.ucsd.edu/A-News/ This Usenet Oldnews Archive article may be copied and distributed freely, provided: 1. There is no money collected for the text(s) of the articles. 2. The following notice remains appended to each copy: The Usenet Oldnews Archive: Compilation Copyright (C) 1981, 1996 Bruce Jones, Henry Spencer, David Wiseman.