ON STRONGLY CONNECTED ORIENTATIONS OF GRAPHS

If it is incident with a 3-face, then the other two vertices on the same face must be of degree at least 5 and this implies that v receives at least 2 5 from its incident faces..

In [2] Bereˇzn´y, Cechl´arov´a and Lacko showed that the spanning tree, match- ing and path problems considered with the L 3 objective function are NP complete already on

We prove that if D is an m-coloured 3-quasitransitive digraph such that for every vertex u of D, A + (u) is monochromatic and D satisfies some colouring conditions over one

Hence, the class of dual-chordal 3-regular graphs mentioned in Theorem 8 is the class of 3-connected, 3-regular dual-chordal graphs that is characterized five ways in [7, §3], one

The vertex/edge labeling considered here is similar to that used in studying mod sum* graphs (see p. 113 of [2]) in that every graph in this paper is a mod sum* graph, but not every

Universidad Nacional Aut´ onoma de M´ exico Ciudad Universitaria, M´ exico

, f 9 of the path P 5 of order 5 (where the vertex labels are shown above each vertex and the induced edge labels are shown below each edge)... This gives us the following

We prove that if D is an m-coloured quasi-transitive digraph such that for every vertex u of D the set of arcs that have u as initial end point is monochromatic and D contains no C