Polar graphs and railway traffic
Positive knots, closed braids and the Jones polynomial
Using the recent Gauß diagram formulas for Vassiliev invariants of Polyak-Viro-Fiedler and combining these formulas with the Bennequin inequality, we prove several inequalities for positive knots relating their Vassiliev invariants, genus and degrees of the Jones polynomial. As a consequence, we prove that for any of the polynomials of Alexander/Conway, Jones, HOMFLY, Brandt-Lickorish-Millett-Ho and Kauffman there are only finitely many positive knots with the same polynomial and no positive knot...
Použitie samočinných počítačov pri skúmání istých rozkladov kompletného grafu
Prime ideals in the lattice of additive induced-hereditary graph properties
An additive induced-hereditary property of graphs is any class of finite simple graphs which is closed under isomorphisms, disjoint unions and induced subgraphs. The set of all additive induced-hereditary properties of graphs, partially ordered by set inclusion, forms a completely distributive lattice. We introduce the notion of the join-decomposability number of a property and then we prove that the prime ideals of the lattice of all additive induced-hereditary properties are divided into two groups,...
Probabilistic reconstruction from subgraphs
Problemas da teoria dos grafos e a sua relação com os problemas da cobertura e da partição de um conjunto
Problems from the world surrounding perfect graphs
Problems in algebraic combinatorics.
Proof of Simoes-Pereira's conjectures on locally k-degenerate graphs.
Propriétés combinatoires, ergodiques et arithmétiques de la substitution de Tribonacci
Nous étudions certaines propriétés combinatoires, ergodiques et arithmétiques du point fixe de la substitution de Tribonacci (introduite par G. Rauzy) et de la rotation du tore qui lui est associée. Nous établissons une généralisation géométrique du théorème des trois distances et donnons une formule explicite pour la fonction de récurrence du point fixe. Nous donnons des propriétés d’approximation diophantienne du vecteur de la rotation de : nous montrons, que pour une norme adaptée, la suite...
Pure circuits in cube graphs
Quasi-radicals and Radicals in Categories
Randomly complete -partite graphs
Recherche des graphes des matrices de Coxeter hyperboliques d’ordre
Reconstructing a Graph from the Incidence Relation on its Edge Set
Reconstruction of a tree from certain maximal proper subtrees
Reducible properties of graphs
Let L be the set of all hereditary and additive properties of graphs. For P₁, P₂ ∈ L, the reducible property R = P₁∘P₂ is defined as follows: G ∈ R if and only if there is a partition V(G) = V₁∪ V₂ of the vertex set of G such that and . The aim of this paper is to investigate the structure of the reducible properties of graphs with emphasis on the uniqueness of the decomposition of a reducible property into irreducible ones.
Reduction and irreducibility for words and tree-words
Regular Graphs, Each Edge of Which Belongs to Exactly One -Gon
Regular societies without short cycles