Abstract We investigate finite non-Abelian simple groups G for which the projective cover of trivial module coincides with permutation on a subgroup and classify all cases unless is Lie type in defining characteristic.

We introduce indecomposable (hooked) Skolem sequences and we show their existence for all admissible orders. We then introduce a new construction for two-fold triple systems from two-fold Skolem sequences, and use this to motivate the concept of a two-fold Rosa sequence, whose existence we show for all admissible orders.

Let be an artin algebra and denote by mod(() the category of nitely generated-modules. Apart from those we are also interested in-modules which are not nitely generated. These are called large. Recall that the algebra is of innnite representation type provided that mod(() has innnitely many isomorphism classes of indecomposable objects. A theorem of Auslander asserts that there exists a large i...

Since D. G. Higman proved that bounded representation type and finite representation type are equivalent for group algebras at prime characteristic, there has been a renewed interest in the Brauer-Thrall conjecture that bounded representation type implies finite representation type for arbitrary algebras. The main purpose of this paper is to present a new approach to this conjecture by showing ...

In [l] Bing constructed a 1-dimensional hereditarily indecomposable continuum which is the inverse limit of a sequence of circles Ct and such that the maps/*: C —>C;_i were of degree 1. In this paper we show that the dimension cannot be raised, i.e., if 5 = Lim(54 , /,-) where St is an TV-sphere and fi is essential, then 5 is not hereditarily indecomposable. In doing so we further generalize Bi...

This work studies how goal-directed agents can form profitable coalitions. A coalition is formed when some agents agree to cooperate for the achievement of a shared goal or to exchange with each other the achievement of their own goals. Assuming that coalition formation processes are supported by unanimous and enforced agreements, we define two qualitative criteria: the do-ut-des property and t...

In this paper we prove the existence of uncountably many indecomposable continua in the dynamics of complex exponentials of the form Eλ(z) = λe z with λ > 1/e. These continua contain points that share the same itinerary under iteration of Eλ. These itineraries are bounded but consist of blocks of 0’s whose lengths increase, and hence these continua are never periodic.