- #1
Bashyboy
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- 5
Homework Statement
Suppose that ##\phi : \mathbb{Z}_n \rightarrow \mathbb{Z}_n##, where the rule is ##\phi([a]_n) = [ka]_n##. Formulate and prove a conjecture that gives necessary and sufficient conditions on the positive integers ##k## and ##n## which would guarantee that ##\phi## is an isomorphism.
Homework Equations
The Attempt at a Solution
I have already shown that is function is a homomorphism. After having worked with a few examples, I found that if either ##n## or ##k## can divide the other number, then ##\phi## would not be an isomorphism. When they say that they want me to give necessary and sufficient conditions, does that mean they want to prove that
"##\phi## is an isomorphism iff ##k## or ##n## do not divide each other?"
The only thing that troubles me is that there may be more restrictions upon ##k##.