Re: multiplicative group question

From: David Wagner (
Date: 07/03/05

Date: Sun, 3 Jul 2005 21:09:06 +0000 (UTC)

Kristian Gjøsteen wrote:
>Isn't the following a trivial example? Hom(Z_n*,Z_n*) is a ring, [..]

How do you represent elements of Hom(Z_n*,Z_n*) efficiently?
I don't see any way other than simply listing the truth table
of the mapping -- which is not a polynomial-size representation.