Free Cyclic Submodules and Non-Unimodular Vectors
arXiv:1107.3050
Abstract
Given a finite associative ring with unity, , and its two-dimensional left module, , the following two problems are addressed: 1) the existence of vectors of that do not belong to any free cyclic submodule (FCS) generated by a unimodular vector and 2) conditions under which such (non-unimodular) vectors generate FCSs. The main result is that for a non-unimodular vector to generate an FCS of , must have at least two maximal right ideals of which at least one is non-principal.
8 pages, no figures; V2 - some theorems slightly reworked, text polished and a reference added