# How to type the symbol for permutation?

• Apr 26th 2008, 07:09 AM
zepher
How to type the symbol for permutation?
like combination/choose, nCr is $n \choose r$

I can't seem to find the code for it. Thanks!
• Apr 26th 2008, 07:14 AM
Moo
Hello,

I've went to wikipedia, so excuse me if it doesn't correspond to the writing you know..

$_{n} P_{r}$ : _{n} P_{r}

Or sometimes : $P_{r}^{n}$ : P_{r}^{n}
• Apr 26th 2008, 08:11 AM
Mathstud28
Quote:

Originally Posted by Moo
Hello,

I've went to wikipedia, so excuse me if it doesn't correspond to the writing you know..

$_{n} P_{r}$ : _{n} P_{r}

Or sometimes : $P_{r}^{n}$ : P_{r}^{n}

Yeah I think that Moo is correct...that is what I use to represent permuatation here
• Apr 26th 2008, 08:21 AM
Isomorphism
For "choose" , I generally use [tex]n \choose r [/tex].
However there is an alternative, which Plato uses:[tex]{\binom{n}{r}} [/tex] which also gives ${\binom{n}{r}}$

Why would they keep 2 symbols for the same representation(Wondering)
• Apr 26th 2008, 08:35 AM
Moo
Perhaps some people don't know about the probability one but know about the polynomial one ? Or vice-versa ? :D