Date: Dec 4, 2012 3:30 PM
Author: Dr J R Stockton
Subject: Re: No Putnam spoilers please

In sci.math message <Pine.NEB.4.64.1212021939320.2621@panix2.panix.com>,
Sun, 2 Dec 2012 19:47:28, William Elliot <marsh@panix.com> posted:

>On Sat, 1 Dec 2012, William Elliot wrote:

>>
>> "What's 5^2012 mod 7?" is a Putnam question? ;-}
>>

>What the heck, just to add some math, I'll solve it,
>Putnam question or not.
>
>phi(7) = 6; 5^2012 = 5^(6 * 335 + 2) = 5^2 = 25 = 4 (mod 7)


Correct by direct calculation in Bases 7, 10, 13, using my longcalc.exe.

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