On the excedance number of colored permutation groups.
On the excluded minors for matroids of branch-width three.
On the existence of (196,91,42) Hadamard difference sets
On the existence of 1-factors in partial squares of graphs
On the existence of a -factor in the fourth power of a graph
On the existence of a cycle of length at least 7 in a (1,≤ 2)-twin-free graph
We consider a simple, undirected graph G. The ball of a subset Y of vertices in G is the set of vertices in G at distance at most one from a vertex in Y. Assuming that the balls of all subsets of at most two vertices in G are distinct, we prove that G admits a cycle with length at least 7.
On the Existence of an Infinite Family of Simple 5-Designs.
On the Existence of Certain Graphs with Diameter Two
On the existence of critically n-connected graphs
On the existence of graphs with a certain ordering of vertices
On the existence of -SOLSSOMs.
On the Existence of (k,l)-Kernels in Infinite Digraphs: A Survey
Let D be a digraph, V (D) and A(D) will denote the sets of vertices and arcs of D, respectively. A (k, l)-kernel N of D is a k-independent (if u, v ∈ N, u 6= v, then d(u, v), d(v, u) ≥ k) and l-absorbent (if u ∈ V (D) − N then there exists v ∈ N such that d(u, v) ≤ l) set of vertices. A k-kernel is a (k, k −1)-kernel. This work is a survey of results proving sufficient conditions for the existence of (k, l)-kernels in infinite digraphs. Despite all the previous work in this direction was done for...
On the existence of MOLS with equal-sized holes.
On the Existence of Room Squares
On the Existence of Room Squares of Order 4n
On the existence of super-single designs with block size 4.
On the expectation and variance of the reversal distance.
On the exponent of -regular primitive matrices.
On the Extension of Graphs with a Given Diameter without Superfluous Edges
On the - and -triangle of the barycentric subdivision of a simplicial complex
For a simplicial complex we study the behavior of its - and -triangle under the action of barycentric subdivision. In particular we describe the - and -triangle of its barycentric subdivision . The same has been done for - and -vector of by F. Brenti, V. Welker (2008). As a consequence we show that if the entries of the -triangle of are nonnegative, then the entries of the -triangle of are also nonnegative. We conclude with a few properties of the -triangle of .