Re: Division in a prime modulus

In article <1192110818.734848.193890@xxxxxxxxxxxxxxxxxxxxxxxxxxx>,
Ian Parker <ianparker2@xxxxxxxxx> wrote:
On 11 Oct, 14:33, magi...@xxxxxxxxxxxxxxxxx (Arturo Magidin) wrote:
In article <1192101762.955415.136...@xxxxxxxxxxxxxxxxxxxxxxxxxxx>,
Ian Parker <ianpark...@xxxxxxxxx> wrote:

Some time ago there was an enquiry which boiled down to this question.

Let p be a prime number.

then x^(p-1) =1 (Mod p)

Only true if p does not divide x.

So that x^(p-2) = x (Mod p)

This does not follow!

Sorry I meant 1/x

Not quite correct either, since 1/x will in general not be an integer,
and you were working with integers, were you not?


--
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"It's not denial. I'm just very selective about
what I accept as reality."
--- Calvin ("Calvin and Hobbes" by Bill Watterson)
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Arturo Magidin
magidin-at-member-ams-org

.

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