On the le-semigroups whose semigroup of bi-ideal elements is a normal band

• Published in: Algebra and Discrete Mathematics
• Date: 2015
• Main Authors: Bhuniya, A.K., Kumbhakar, M.
• Format: Article
• Language: English
• Published: Інститут прикладної математики і механіки НАН України 2015
• Online Access: https://nasplib.isofts.kiev.ua/handle/123456789/155148
• Journal Title: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Cite this: On the le-semigroups whose semigroup of bi-ideal elements is a normal band / A.K. Bhuniya, M. Kumbhakar // Algebra and Discrete Mathematics. — 2015. — Vol. 20, № 2. — С. 171-181. — Бібліогр.: 24 назв. — англ.

It is well known that the semigroup B(S) of all bi-ideal elements of an le-semigroup S is a band if and only if S is both regular and intra-regular. Here we show that B(S) is a band if and only if it is a normal band and give a complete characterization of the le-semigroups S for which the associate...