Subset Permutations One interesting result is kPn: (!n)%(!n-k) permutations of n unique items in k places, or ordered subsets of k items from set of unique n ones.
http://mathworld.wolfram.com/Permutation.html load'viewmat' kPn1=: [EMAIL PROTECTED]@[ /:~@(,/)@:(A."1) comb ([EMAIL PROTECTED] viewmat) 3 kPn1 4 24 3 which by observing the spectrum is the same as kPn2=: - ~.@:(}."1) ([EMAIL PROTECTED] A. i.)@] ([EMAIL PROTECTED] viewmat) 3 kPn2 4 24 3 3 (kPn1 (-: , [EMAIL PROTECTED]) kPn2) 5 1 60 3 3 (kPn1 (-: , [EMAIL PROTECTED]) kPn2) 6 1 120 3 3 (] %&! -~) 4 5 6 24 60 120 --- Roger Hui <[EMAIL PROTECTED]> wrote: > What is the answer supposed to be? > > > > ----- Original Message ----- > From: "bill lam" <[EMAIL PROTECTED]> > To: <[email protected]> > Sent: Monday, March 06, 2006 10:22 PM > Subject: [Jprogramming] permutation > > how to define a dyad perm similar to comb? > > 3 comb 5 > 0 1 2 > 0 1 3 > 0 1 4 > 0 2 3 > 0 2 4 > 0 3 4 > 1 2 3 > 1 2 4 > 1 3 4 > 2 3 4 > > 3 perm 5 > |index error: perm > | 3 perm 5 > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
