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Skein algebras of the solid torus and symmetric spatial graphs

Nafaa Chbili (2006)

Fundamenta Mathematicae

We use the topological invariant of spatial graphs introduced by S. Yamada to find necessary conditions for a spatial graph to be periodic with a prime period. The proof of the main result is based on computing the Yamada skein algebra of the solid torus and then proving that it injects into the Kauffman bracket skein algebra of the solid torus.

Some crossing numbers of products of cycles

Marián Klešč (2005)

Discussiones Mathematicae Graph Theory

The exact values of crossing numbers of the Cartesian products of four special graphs of order five with cycles are given and, in addition, all known crossing numbers of Cartesian products of cycles with connected graphs on five vertices are summarized.

Some recent results on domination in graphs

Michael D. Plummer (2006)

Discussiones Mathematicae Graph Theory

In this paper, we survey some new results in four areas of domination in graphs, namely: (1) the toughness and matching structure of graphs having domination number 3 and which are "critical" in the sense that if one adds any missing edge, the domination number falls to 2; (2) the matching structure of graphs having domination number 3 and which are "critical" in the sense that if one deletes any vertex, the domination number falls to 2; (3) upper bounds...

Stability of graphs.

Demir, Bünyamin, Deniz, Ali, Koçak, Sahin (2009)

The Electronic Journal of Combinatorics [electronic only]

Statuses and double branch weights of quadrangular outerplanar graphs

Halina Bielak, Kamil Powroźnik (2015)

Annales UMCS, Mathematica

In this paper we study some distance properties of outerplanar graphs with the Hamiltonian cycle whose all bounded faces are cycles isomorphic to the cycle C4. We call this family of graphs quadrangular outerplanar graphs. We give the lower and upper bound on the double branch weight and the status for this graphs. At the end of this paper we show some relations between median and double centroid in quadrangular outerplanar graphs

Strong Chromatic Index Of Planar Graphs With Large Girth

Gerard Jennhwa Chang, Mickael Montassier, Arnaud Pêche, André Raspaud (2014)

Discussiones Mathematicae Graph Theory

Let Δ ≥ 4 be an integer. In this note, we prove that every planar graph with maximum degree Δ and girth at least 1 Δ+46 is strong (2Δ−1)-edgecolorable, that is best possible (in terms of number of colors) as soon as G contains two adjacent vertices of degree Δ. This improves [6] when Δ ≥ 6.

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