Some Investigations on Orthogonal Arrays

Abstract

In this paper we obtain some results on orthogonal arrays $(O-arrays)$ of strength six by considering balanced arrays $(B-arrays)$ of strength six with ${\underset{\_}{\mu }}^{\prime }=(\mu –1,\mu ,\mu ,\mu ,\mu ,\mu ,\mu –1)$ which we call Near O-arrays. As a consequence we demonstrate that we obtain better bounds on the number of constraints for some O-arrays as compared to those given by Rao (1947).