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Kvothe
12/13/12 10:55am

Hello,

I'd like to assess the following expression:

1-2+5-...+-(2^n - n)

which should be presented as a "Sum".

Sum[f, {i=0,n}]

Now I thought about defining this expression:
it's MINUS for n = straight number
it's PLUS for n = odd number

F.e.:

n= 3 -> +(2^3 - 2) = +5
n=2 -> - (2^2 - 2) = -2


How can I do this? Or is there a simplier way?

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Subject (listing for 'Sum - Definition')
Author Date Posted
Sum - Definition Kvothe 12/13/12 10:55am
Re: Sum - Definition Nasser M. Ab... 12/13/12 11:36am
Re: Sum - Definition Bill Simpson 12/14/12 11:09am
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