Re: Math Problem
- From: Bill Dubuque <wgd@xxxxxxxxxxxxxxxxxxxx>
- Date: 31 Jul 2007 03:16:01 -0400
Gene Wirchenko <genew@xxxxxxxx> wrote: (*edited*)
a = b^c, a,b,c,d,e integers.
b mod 8 is neither 1 nor prime.
b is even, not 1,3,5,7 mod 8
c = e 2^d, d prime, e = d^2 - 3
4 | c > 0 via d >= 2
not 5|a(b + c)(d + e)
not 5|b, else 5 | b^c = a contra prior
In simplest terms, what is the remainder when a is divided by 10?
a = b^c, not 5|b, 4|c -> a = 1 (mod 5) by Fermat's Little Theorem
b even -> a even -> a = 6 (mod 10)
--Bill Dubuque
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