International Journal of Mathematics and Mathematical Sciences
Volume 14 (1991), Issue 2, Pages 293-304
doi:10.1155/S0161171291000340
On the semi-sub-hypergroups of a hypergroup
54 Klious Street, Cholargos, Athens 155 61, Greece
Received 20 October 1987; Revised 5 December 1989
Copyright © 1991 Ch. G. Massouros. 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
In this paper we study some properties of the semi-sub-hypergroups and the
closed sub-hypergroups of the hypergroups. We introduce the correlated elements and
the fundamental elements and we connect the concept antipodal of the latter with
Frattin's hypergroup. We also present Helly's Theorem as a corollary of a more
general Theorem.