The achromatic number (G) of a graph G = (V, E) is the maximum k such that V has a partition V1, V2, . . . , Vk into independent sets, the union of no pair of which is independent...
The crossing number, cr(G), of a graph G is the least number of crossing points in any drawing of G in the plane. According to the Crossing Lemma of Ajtai, Chv´atal, Newborn, Sze...
Let G = (V, E) be a simple graph on vertex set V and define a function f : V {-1, 1}. The function f is a signed dominating function if for every vertex x V, the closed neighbor...
We prove that for sufficiently large n, there exist unit disk graphs on n vertices such that for every representation with disks in the plane at least c √ n bits are needed to wr...