MathGroup Archive 1997

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Help ! complex permutations

  • To: mathgroup at
  • Subject: [mg7045] Re: [mg6965] Help ! complex permutations
  • From: "w.meeussen" <w.meeussen.vdmcc at>
  • Date: Sat, 3 May 1997 22:04:39 -0400 (EDT)
  • Sender: owner-wri-mathgroup at

At 22:25 30-04-97 -0400, Robert Perkins wrote:
>I need to derive an algorithm, formula, which gives all the
>possiblities, combinations, for any 'n' out of 'm' with the proviso
>that any member of 'm' can be used multiple times and the selection
>sequence is significant. 
>Taking a trivial example if the input list 'm' is
>	{a,b} 
>the output list 'n' for any 2 gives
>	{a,a},{a,b},{b,a},{b,b}
>For an output sequence of 3 from the same input list would give
>	{a,a,a},{a,a,b},{a,b,b},{b,a,b},{b,b,a},{b,b,b}
>Life gets interesting for larger input sequences and ever larger
>output selections. How about the input list containing 10 members and
>the output list containing 20 members with the above rules applying?
>Can anyone point me in the right direction? A reference, clue or even
>an algorithm would be very welcome ;)
look at Outer[List,{a,b},{a,b},{a,b}]

Dr. Wouter L. J. MEEUSSEN
eu000949 at
w.meeussen.vdmcc at

  • Prev by Date: backets for non-american keybords, 2.2.3
  • Next by Date: Re: Help ! complex permutations
  • Previous by thread: Re: Help ! complex permutations
  • Next by thread: Re: Help ! complex permutations