International Journal of Computer Mathematics, 97(1-2), p. 431-443 (2019); doi:10.1080/00207160.2019.1642470
Amatrix is sign regular if all its minors of the same order are of the same sign. A very important subclass of sign regular matrices is formed by those matrices whose non-trivial minors are non-zero. These matrices are called almost strictly sign regular matrices. In this work, an algorithmic characterization of pentadiagonal almost strictly sign regular matrices is presented.