Simplicial approximation and low-rank trees.
Singular Hecke algebras, Markov traces, and HOMFLY-type invariants
We define the singular Hecke algebra as the quotient of the singular braid monoid algebra by the Hecke relations , . We define the notion of Markov trace in this context, fixing the number of singular points, and we prove that a Markov trace determines an invariant on the links with singular points which satisfies some skein relation. Let denote the set of Markov traces with singular points. This is a -vector space. Our main result is that is of dimension . This result is completed...
Singularités génériques des variétés de Schubert covexillaires
On montre que les composantes irréductibles du lieu singulier d’une variété de Schubert dans associée à une permutation covexillaire, sont paramétrées par certains des points coessentiels du graphe de la permutation. On donne une description explicite de ces composantes et l’on décrit la singularité le long de chacune d’entre elles.
is not boundedly generated by elementary matrices: explicit proof.
Small Cancellation Conditions Satisfield by One-Relator Groups.
Small cancellation theory and automatic groups.
Small cancellation theory and automatic groups: Part II.
Small maximal sum-free sets.
Soluble Groups with Many Černikov Quotients
Si studiano i gruppi risolubili non di Černikov a quozienti propri di Černikov. Nel caso periodico tali gruppi sono tutti e soli i prodotti semidiretti con -gruppo abeliano elementare infinito e gruppo irriducibile di automorfismi di che sia infinito e di Černikov. Nel caso non periodico invece si riconduce tale studio a quello dei moduli a quozienti...
Soluble Groups with the Minimum Condition for Normal Subgroups.
Soluble products of nilpotent groups
Soluble Products of Polycyclic Groups.
Soluble products of two locally finite groups with min- for every prime
Solvable Groups that are Simply Connected at ... .
Solvable groups with many BFC-subgroups.
We characterize the solvable groups without infinite properly ascending chains of non-BFC subgroups and prove that a non-BFC group with a descending chain whose factors are finite or abelian is a Cernikov group or has an infinite properly descending chain of non-BFC subgroups.
Solvable infinite-dimensional linear groups with restrictions on the nonabelian subgroups of infinite rank.
Solvable systems of equations modeled on some spines of 3-manifolds.
Solvable word problems in semigroups.
Some Algebraic Properties of Machine Poset of Infinite Words
The complexity of infinite words is considered from the point of view of a transformation with a Mealy machine that is the simplest model of a finite automaton transducer. We are mostly interested in algebraic properties of the underlying partially ordered set. Results considered with the existence of supremum, infimum, antichains, chains and density aspects are investigated.
Some aspects of radical theory for fully ordered Abelian groups