Abstract. Let [X/G] be an orbifold which is a global quotient of a compact almost complex manifold X by a finite group G. Let Σn be the symmetric group on n letters. Their semidirect product G ⋊ Σn is called the wreath product of G and it naturally acts on the n-fold product X, yielding the orbifold [X/(G ⋊Σn)]. Let H (X , G ⋊Σn) be the stringy cohomology [FG, JKK1] of the (G ⋊ Σn)-space X . Wh...

A permutation class which is closed under pattern involvement may be described in terms of its basis. The wreath product construction X o Y of two permutation classes X and Y is also closed, and we investigate classes Y with the property that, for any finitely based class X, the wreath product X o Y is also finitely based.

We study the minimal non-trivial subdegrees of finite primitive permutation groups that admit an embedding into a wreath product in product action, giving a connection with the same quantity for the primitive component. We discover that the primitive groups of twisted wreath type exhibit different (but interesting) behaviour from the other primitive types. 2000 Mathematics Subject Classificatio...

We systematically study wreath product Schur functions and give a combinatorial construction using colored partitions and tableaux. The Pieri rule and the Littlewood-Richardson rule are studied. We also discuss the connection with representations of generalized symmetric groups.

In this paper we prove two main results. The first is a necessary and sufficient condition for a semidirect product of a semilattice by a group to be finitely generated. The second result is a necessary and sufficient condition for such a semidirect product to be finitely presented. 2000 Mathematics subject classification: primary 20M05; secondary 20M18, 20M30.

We prove that the wreath product orbifolds studied earlier by the first author provide a large class of higher dimensional examples of orbifolds whose orbifold Hodge numbers coincide with the ordinary ones of suitable resolutions of singularities. We also make explicit conjectures on elliptic genera for the wreath product orbifolds.