DM
2002
13 years 4 months ago
2002
It is shown that in a 4-connected maximal planar graph there is for any four vertices a, b, c and d, a cycle in the graph that contains the four vertices and visits them in the or...
DM
2002
13 years 4 months ago
2002
Consider the minimum number f(m, n) of zeroes in a 2m
DM
2002
13 years 4 months ago
2002
An approach to the computations of upper bounds on the size of large complete arcs is presented. In particular, we obtain geometrical properties of irreducible envelopes associated...
DM
2002
13 years 4 months ago
2002
We outline the computation of an explicit formula for the Hilbert function of the ladder determinantal varieties defined by the vanishing of all minors of a fixed size of a rectang...
DM
2002
13 years 4 months ago
2002
In this paper, we present several conditions for K1,3-free graphs, which guarantee the graph is subpancyclic. In particular, we show that every K1,3-free graph with minimum degree...
DM
2002
13 years 4 months ago
2002
We present here a proof that a certain rational function Cn(q, t) which has come to be known as the "q, t-Catalan" is in fact a polynomial with positive integer coeffici...
DM
2002
13 years 4 months ago
2002
DM
2002
13 years 4 months ago
2002
Balanced nested designs are closely related to other combinatorial structures such as balanced arrays and balanced n-ary designs. In particular, the existence of symmetric balance...
DM
2002
13 years 4 months ago
2002
DM
2002
13 years 4 months ago
2002
A star forest of a graph G is a spanning subgraph of G in which each component is a star. The minimum number of edges required to guarantee that an arbitrary graph, or a bipartite...