The skew-growth function on the monoid of square matrices

We develop an elementary theory of divisibility on the monoid $M(n,R)^\times$ consisting of all square matrices of size $n\ge 1$ of non-zero determinants with coefficients in a principal ideal domain $R$. In particular, we show that any finite subset of the monoid has the least left common multiple up to a right unit factor. When $R$ is residue finite, we consider a signed generating series, called the skew growth function, of least common multiples of finite right equivalence classes of irreducible elements. As an elementary application of the divisibility theory, we show that the skew-growth function decomposes into Euler products.