Fuzzy bi-ideals play an important role in the study of ordered semigroupstructures. The purpose of this paper is to initiate and study theintiuitionistic fuzzy bi-ideals in ordered semigroups and investigate thebasic theorem of intuitionistic fuzzy bi-ideals. To provide thecharacterizations of regular ordered semigroups in terms of intuitionisticfuzzy bi-ideals and to discuss the relationships ...

A finite group $G$ is called rational if all its irreducible complex characters are rational valued. In this paper we discuss about rational groups with Sylow 2-subgroups of nilpotency class at most 2 by imposing the solvability and nonsolvability assumption on $G$ and also via nilpotency and nonnilpotency assumption of $G$.

In this paper, we study the structure of nite Frobenius groups whose non-rational or non-real irreducible characters are linear.

In this article, we show that every rational map whose multipliers all lie in a given number field is power map, Chebyshev or Lattès map. This strengthens conjecture by Milnor concerning maps with integer multipliers, which was recently proved Ji and Xie.