Calcul du centralisateur d'un groupe de permutations
Cayley color graphs of inverse semigroups and groupoids
The notion of Cayley color graphs of groups is generalized to inverse semigroups and groupoids. The set of partial automorphisms of the Cayley color graph of an inverse semigroup or a groupoid is isomorphic to the original inverse semigroup or groupoid. The groupoid of color permuting partial automorphisms of the Cayley color graph of a transitive groupoid is isomorphic to the original groupoid.
Characterisation of Some Steiner Systems, Parallelisms, and Biplanes.
Chohomological Aspects of Two-Graphs.
Completely 0-simple semigroups and their associated graphs and groups.
Congruence classes of orientable 2-cell embeddings of bouquets of circles and dipoles.
Construction of finite -groups with prescribed group of noncentral automorphisms