Date: Oct 16, 2009 8:23 AM
Subject: n square free) ^ ( d I n and u = v (mod d) --> f(u) = f(v) (mod d) ) <br>	--> (f is a polynomial over Z_n)

How can I show that for any squarefree n and function f  from Z_n to
Z_n that has the propery that- whenever d I n and u = v (mod d) then f
(u) = f(v) (mod d) - must be a polynomial over Z_n ?