On acyclic hypergraphs of minimal prime models.
On Alperin's fusion theorem.
On alternating products of graph relations.
On amalgamation of graphs and essential sets of generators
On amply regular graphs with .
On an algorithm to decide whether a free group is a free factor of another
We revisit the problem of deciding whether a finitely generated subgroup is a free factor of a given free group . Known algorithms solve this problem in time polynomial in the sum of the lengths of the generators of and exponential in the rank of . We show that the latter dependency can be made exponential in the rank difference rank - rank, which often makes a significant change.
On an algorithm to decide whether a free group is a free factor of another
We revisit the problem of deciding whether a finitely generated subgroup H is a free factor of a given free group F. Known algorithms solve this problem in time polynomial in the sum of the lengths of the generators of H and exponential in the rank of F. We show that the latter dependency can be made exponential in the rank difference rank(F) - rank(H), which often makes a significant change.
On an evaluation function for heuristic search as a path problem
On an extremal problem concerning graphs (Preliminary communication)
On an extremal problem in graph theory
On An Extremal Problem In The Class Of Bipartite 1-Planar Graphs
A graph G = (V, E) is called 1-planar if it admits a drawing in the plane such that each edge is crossed at most once. In this paper, we study bipartite 1-planar graphs with prescribed numbers of vertices in partite sets. Bipartite 1-planar graphs are known to have at most 3n − 8 edges, where n denotes the order of a graph. We show that maximal-size bipartite 1-planar graphs which are almost balanced have not significantly fewer edges than indicated by this upper bound, while the same is not true...
On an identity for the cycle indices of rooted tree automorphism groups.
On Arbitrarily Traceable Graphs.
On arbitrarily vertex decomposable unicyclic graphs with dominating cycle
A graph G of order n is called arbitrarily vertex decomposable if for each sequence (n₁,...,nₖ) of positive integers such that , there exists a partition (V₁,...,Vₖ) of vertex set of G such that for every i ∈ 1,...,k the set induces a connected subgraph of G on vertices. We consider arbitrarily vertex decomposable unicyclic graphs with dominating cycle. We also characterize all such graphs with at most four hanging vertices such that exactly two of them have a common neighbour.
On arc-coloring of subcubic graphs.
On asymptotic stability of passive linear electrical networks
On automorphisms of digraphs without symmetric cycles
A digraph is a symmetric cycle if it is symmetric and its underlying graph is a cycle. It is proved that if is an asymmetric digraph not containing a symmetric cycle, then remains asymmetric after removing some vertex. It is also showed that each digraph without a symmetric cycle, whose underlying graph is connected, contains a vertex which is a common fixed point of all automorphisms of .
On automorphisms of strongly regular graphs with and . II.
On balancing of hypergraphs
On bandwidth, cutwidth, and quotient graphs