Olivier Baudon y, Guillaume Fertin y and Ivan Havel z y LaBRI U.M.R. CNRS 5800, Universit e Bordeaux I 351 Cours de la Lib eration, F33405 Talence Cedex z Faculty of Mathematics and Physics, Charles University Malostransk e n am. 25, 118 00 Praha, Czech Republic fbaudon,[email protected], [email protected] Abstract We study an n-dimensional directed symmetric hypercube Hn, in which e...

We begin by giving some background to this result. A matroid M is an excluded minor for a minor-closed class of matroids if M is not in the class but all proper minors of M are. It is natural to attempt to characterize a minor-closed class of matroids by giving a complete list of its excluded minors. Unfortunately, a minor-closed class of matroids can have an infinite number of excluded minors....

Suppose that a finite group G admits a Frobenius group of automorphisms FH with kernel F and complement H such that the fixed-point subgroup of F is trivial: CG(F ) = 1. In this situation various properties of G are shown to be close to the corresponding properties of CG(H). By using Clifford’s theorem it is proved that the order |G| is bounded in terms of |H| and |CG(H)|, the rank of G is boun...

You will say that my title is absurd. "Mathematical papers cannot be totally ordered. It's a great pity! Poor old Coleman has obviously gone berserk in his old age." Please read on. If in 1940 you had asked the starry-eyed Canadian graduate student who was lapping up the K-calculus from Alonzo Church in Princeton to name the single most important mathematics paper, without doubt I would have ch...

‎we investigate graham higman's paper enumerating $p$-groups‎, ‎ii‎, ‎in which he formulated his famous porc conjecture‎. ‎we are able to simplify some of the theory‎. ‎in particular‎, ‎higman's paper contains five pages of homological algebra which he uses in‎ ‎his proof that the number of solutions in a finite field to a finite set of‎ ‎monomial equations is porc‎. ‎it turns out tha...

We prove a strong form of the Brumer–Stark Conjecture and, as a consequence, a strong form of Rubin’s integral refinement of the abelian Stark Conjecture, for a large class of abelian extensions of an arbitrary characteristic p global field k. This class includes all the abelian extensions K/k contained in the compositum kp∞ := kp · k∞ of the maximal pro-p abelian extension kp/k and the maximal...

We give a polynomial counterexample to a discrete version of the Markus-Yamabe Conjecture and a conjecture of Deng, Meisters and Zampieri, asserting that if F : C → C is a polynomial map with det(JF ) ∈ C∗, then for all λ ∈ R large enough λF is global analytic linearizable. These counterexamples hold in any dimension ≥ 4.

We give a polynomial counterexample to both the Markus-Yamabe Conjecture and the discrete Markus-Yamabe problem for all dimensions ≥ 3.