À propos d’un lemme de Ribet
A quantitative aspect of non-unique factorizations: the Narkiewicz constants III
Let K be an algebraic number field with non-trivial class group G and be its ring of integers. For k ∈ ℕ and some real x ≥ 1, let denote the number of non-zero principal ideals with norm bounded by x such that a has at most k distinct factorizations into irreducible elements. It is well known that behaves for x → ∞ asymptotically like . We prove, among other results, that for all integers n₁,n₂ with 1 < n₁|n₂.
A quantitative aspect of non-unique factorizations: the Narkiewicz constants II
Let K be an algebraic number field with non-trivial class group G and be its ring of integers. For k ∈ ℕ and some real x ≥ 1, let denote the number of non-zero principal ideals with norm bounded by x such that a has at most k distinct factorizations into irreducible elements. It is well known that behaves, for x → ∞, asymptotically like . In this article, it is proved that for every prime p, , and it is also proved that if and m is large enough. In particular, it is shown that for...
A radical for free groups
A rank 3 tangent complex of , odd.
A realization of -groups
A reconstruction theorem for locally moving groups acting on completely metrizable spaces
Let G be a group which acts by homeomorphisms on a metric space X. We say the action of G is locally moving on X if for every open U ⊆ X there is a g ∈ G such that g↾X ≠ Id while g↾(X∖U) = Id. We prove the following theorem: Theorem A. Let X,Y be completely metrizable spaces and let G be a group which acts on X and Y with locally moving actions. If the orbits of the action of G on X are of the second category in X and the orbits of the action of G on Y are of the second category...
A recurrence relation approach to higher order quantum superintegrability.
A Rédei type factorization result for a special 2-group.
A Reducibility Arising from the Boone Groups.
A reduction theorem for complexity of finite semigroups.
A regular a-semigroups inducing a certain lattice.
A regularity criterion for semigroup rings.
A relation between dimension of the harmonic measure, entropy and drift for a random walk on a hyperbolic space.
A Relation for Closure Operations on a Semigroup
A Relative cohomological invariant for group pairs.
A relatively free topological group that is not varietal free
Answering a 1982 question of Sidney A. Morris, we construct a topological group G and a subspace X such that (i) G is algebraically free over X, (ii) G is relatively free over X, that is, every continuous mapping from X to G extends to a unique continuous endomorphism of G, and (iii) G is not a varietal free topological group on X in any variety of topological groups.
A remark about central automorphisms of groups
A remark concerning congruences on [0,-] bisimple inverse semigroups.
A remark concerning -systems