Copyright © 2010 Ahmad N. Al-Kenani. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

It is known that every class-regular symmetric (μ,m)-net is tactical. Also it is known that all (μ,m)-nets with m=2 or μ=1 are tactical. In the work of Al-Kenani and Mavron (2003), it is proved that every symmetric net with m=3 is tactical if and only if it is class regular. In this paper, we construct (2,4)-net and show that it is class regular and therefore tactical. New necessary and sufficient conditions are given for a symmetric net to admit a nonidentity bitranslation.