DM
2008
13 years 11 months ago
2008
In this paper we show that for large primes the Giulietti-Ughi arcs in PG(2, p2) are not complete. In the second half of the paper we extend the original arc. Key words: Arc, Proj...
DM
2008
13 years 11 months ago
2008
Let G be the set that contains precisely the graphs on n vertices with maximum degree 3 for which there exists a 4-cycle system of their complement in Kn. In this paper G is compl...
DM
2008
13 years 11 months ago
2008
We prove that a K4-free graph G of order n, size m and maximum degree at most three has an independent set of cardinality at least 1 7 (4n - m - - tr) where counts the number of c...
DM
2008
13 years 11 months ago
2008
Beatty sequences n + are nearly linear, also called balanced, namely, the absolute value of the difference D of the number of el
DM
2008
13 years 11 months ago
2008
In [2], Duffus et al. showed that every connected graph G which contains no induced subgraph isomorphic to a claw or a net is traceable. And they also showed that if a 2-connected...
DM
2008
13 years 11 months ago
2008
This paper discusses the game colouring number of partial k-trees and planar graphs. Let colg(PT k) and colg(P) denote the maximum game colouring number of partial k trees and the...
DM
2008
13 years 11 months ago
2008
DM
2008
13 years 11 months ago
2008
Fix nonnegative integers n1, . . . , nd and let L denote the lattice of integer points (a1, . . . , ad) Zd satisfying 0 ai ni for 1 i d. Let L be partially ordered by the usua...
DM
2008
13 years 11 months ago
2008
For a simple graph G let NG(u) be the (open) neighborhood of vertex u V (G). Then G is neighborhood anti-Sperner (NAS) if for every u there is a v V (G)\{u} with NG(u) NG(v). A...
DM
2008
13 years 11 months ago
2008
