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Message-ID: <48BC15FB.5050007@witthoft.com>
Date: 2008-09-01T16:19:07Z
From: Carl Witthoft
Subject: give all combinations

I seem to be missing something here:

given a set X:{a,b,c,whatever...}
the mathematical definition of 'permutation' is the set of all possible 
sequences of the elements of X.
The definition of 'combination' is all elements of 'permutation' which 
cannot be re-ordered to become a different element.

example:  X:{a,b,c}

perm(X) = ab, ab, bc, ba, ca, cb
comb(X) = ab, ac, bc


So maybe a better question for this mailing list is:  Are there 
functions available in any R package which produce perm() and comb() 
(perhaps as well as other standard combinatoric functions) ?

Carl