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Re: Re: Simplify (-1)^((-1)^n)

• To: mathgroup at smc.vnet.net
• Subject: [mg76500] Re: [mg76427] Re: Simplify (-1)^((-1)^n)
• From: "Lev Bishop" <lev.bishop at gmail.com>
• Date: Wed, 23 May 2007 05:21:34 -0400 (EDT)
• References: <f2rrer$a4q$1@smc.vnet.net> <200705220645.CAA19692@smc.vnet.net>

On 5/22/07, Peter Pein <petsie at dordos.net> wrote:

> I'm afraid, you have to tell Mathematica, that an integer is either even or odd:
>
> In[1]:=
> $Version
> Assuming[{n, n - 1}/2 \[Element] Integers,
>   Simplify[ComplexExpand[(-1)^(-1)^n]]]
> Out[1]= "5.1 for Microsoft Windows (October 25, 2004)"
> Out[2]= -1


Um... No! You just told mathematica n is even AND odd!

In[3]:=
$Version
Assuming[{n,n-1}/2\[Element]Integers,{Simplify[((n-1)/2)\[Element]Integers],
    Simplify[(n/2)\[Element]Integers]}]
Out[3]=
5.1 for Microsoft Windows (January 28, 2005)
Out[4]=
{True,True}

• References:
  • Re: Simplify (-1)^((-1)^n)
    • From: Peter Pein <petsie@dordos.net>