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A note on face coloring entire weightings of plane graphs

Stanislav Jendrol, Peter Šugerek (2014)

Discussiones Mathematicae Graph Theory

Given a weighting of all elements of a 2-connected plane graph G = (V,E, F), let f(α) denote the sum of the weights of the edges and vertices incident with the face _ and also the weight of _. Such an entire weighting is a proper face colouring provided that f(α) ≠ f(β) for every two faces α and _ sharing an edge. We show that for every 2-connected plane graph there is a proper face-colouring entire weighting with weights 1 through 4. For some families we improved 4 to 3

A note on graph coloring

D. De Werra (1974)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

A note on intersection dimensions of graph classes

Petr Hliněný, Aleš Kuběna (1995)

Commentationes Mathematicae Universitatis Carolinae

The intersection dimension of a graph G with respect to a class 𝒜 of graphs is the minimum k such that G is the intersection of some k graphs on the vertex set V ( G ) belonging to 𝒜 . In this paper we follow [ Kratochv’ıl J., Tuza Z.: Intersection dimensions of graph classes, Graphs and Combinatorics 10 (1994), 159–168 ] and show that for some pairs of graph classes 𝒜 , the intersection dimension of graphs from with respect to 𝒜 is unbounded.

A note on Jeu de Taquin

Rocco Chirivì (1999)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

A direct formula for jeu de taquin applied to the swap of two rows of standard tableaux is given. A generalization of this formula to non standard tableaux is used to describe combinatorially a path basis isomorphism for the algebra of type A l .

A note on joins of additive hereditary graph properties

Ewa Drgas-Burchardt (2006)

Discussiones Mathematicae Graph Theory

Let L a denote a set of additive hereditary graph properties. It is a known fact that a partially ordered set ( L a , ) is a complete distributive lattice. We present results when a join of two additive hereditary graph properties in ( L a , ) has a finite or infinite family of minimal forbidden subgraphs.

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