Modular Arithmetic Inverse of a Rectangular Matrix

Abstract

In this paper, we have devoted our attention to the study of the modular arithmetic inverse of a rectangular matrix. Here, we have shown that (AB) mod N = I, where A is of size m x n and B is of size n x m in which m < n. We have also established that the modular arithme-tic inverse of a rectangular matrix does not exist, when m > n.

Keywords: Rectangular matrix, Arithmetic inverse, Modular arithmetic inverse, Block cipher, Square matrix.