Re: Combinations
- To: mathgroup at smc.vnet.net
- Subject: [mg30821] Re: Combinations
- From: "Graeme Byrne" <g.byrne at bendigo.latrobe.edu.au>
- Date: Wed, 19 Sep 2001 00:17:17 -0400 (EDT)
- Organization: La Trobe University
- References: <9nh2jh$ml$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Dana, try
Count[Permutations[{a, b, c, d, e, f}], _ ]
for the number of permutations of a list of things and
Binomial[a,b]
for the number of combinations of a things taken b at a time
Graeme
"Dana" <ng_only at hotmail.com> wrote in message
news:9nh2jh$ml$1 at smc.vnet.net...
> Hello. I have Mathematica 4.1
>
> In a Program like Excel, or a hand-held calculator, one can return the
> number of combinations and permutations.
>
> However, I can not find an equivalent function in Mathematica.
> For example, Permutations[ ] returns a long list of all the "Actual"
> permutations.
> I am looking for just the final number.
> If there is one, could you include 'how' you found it. I have looked
> everywhere.
> I know DiscreteMath`Combinatorica` has some stuff in it, but the Help
system
> appears not to explain many of them.
>
> I can write a custom function, but I am curious to find out if this
function
> is built in to Mathematica.
>
> I hope the answer is not to take the Length[ ] of a rather long list.
>
> TIA. Dana
>
> (I posted this question a month ago, but it never showed up in the
> newsgroup, or in the archives.
> I hope I am not doing something wrong.)
>
>
>
>
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