Characterization of a radical of group rings over finite prime fields.
Let be a finite group. Let be the first column of the ordinary character table of . We will show that if , then . As a consequence, we show that the projective general unitary groups are uniquely determined by the structure of their complex group algebras.
Each homogeneous space of a quasigroup affords a representation of the Bose-Mesner algebra of the association scheme given by the action of the multiplication group. The homogeneous space is said to be faithful if the corresponding representation of the Bose-Mesner algebra is faithful. In the group case, this definition agrees with the usual concept of faithfulness for transitive permutation representations. A permutation character is associated with each quasigroup permutation representation,...
In this note, we study finite groups possessing exactly one nonlinear non-faithful irreducible character. Our main result is to classify solvable groups that satisfy this property. Also, we give examples to show that these groups need not to be solvable in general.
Let be a finite group with a normal subgroup such that . It is shown that under some conditions, Coleman automorphisms of are inner. Interest in such automorphisms arose from the study of the normalizer problem for integral group rings.