Convex hulls of polyominoes.
Convex independence and the structure of clone-free multipartite tournaments
We investigate the convex invariants associated with two-path convexity in clone-free multipartite tournaments. Specifically, we explore the relationship between the Helly number, Radon number and rank of such digraphs. The main result is a structural theorem that describes the arc relationships among certain vertices associated with vertices of a given convexly independent set. We use this to prove that the Helly number, Radon number, and rank coincide in any clone-free bipartite tournament. We...
Convex Polytopes Whose Projection Bodies and Difference Sets Are Polars.
Convex Representations of Maps on the Torus and Other Flat Surfaces.
Convex universal fixers
In [1] Burger and Mynhardt introduced the idea of universal fixers. Let G = (V, E) be a graph with n vertices and G’ a copy of G. For a bijective function π: V(G) → V(G’), define the prism πG of G as follows: V(πG) = V(G) ∪ V(G’) and , where . Let γ(G) be the domination number of G. If γ(πG) = γ(G) for any bijective function π, then G is called a universal fixer. In [9] it is conjectured that the only universal fixers are the edgeless graphs K̅ₙ. In this work we generalize the concept of universal...
Convex-ear decompositions and the flag -vector.
Convolutions related to q-deformed commutativity
Two important examples of q-deformed commutativity relations are: aa* - qa*a = 1, studied in particular by M. Bożejko and R. Speicher, and ab = qba, studied by T. H. Koornwinder and S. Majid. The second case includes the q-normality of operators, defined by S. Ôta (aa* = qa*a). These two frameworks give rise to different convolutions. In particular, in the second scheme, G. Carnovale and T. H. Koornwinder studied their q-convolution. In the present paper we consider another convolution of measures...
Cooperative guards in art galleries [Book]
Cooperative guards in art galleries with one hole.
Coordinatization of parallel systems. II.
Cordial deficiency.
Cores and shells of graphs
The -core of a graph , , is the maximal induced subgraph such that , if it exists. For , the -shell of a graph is the subgraph of induced by the edges contained in the -core and not contained in the -core. The core number of a vertex is the largest value for such that , and the maximum core number of a graph, , is the maximum of the core numbers of the vertices of . A graph is -monocore if . This paper discusses some basic results on the structure of -cores and -shells....
Correction de mon article ’Sur le nombre des -cycles dans un tournoi’
Correction: “The smallest graph whose group is cyclic”
Correction to "Partial Spreads in Finite Projective Spaces and Partial Designs".
Correction to "The bias of three pseudo-random shuffles", Volume 22, 2/3 (1981), p. 268-292.
Correction to the paper "A note on inequivalent Hadamard matrices".
Correction to the paper: Packing of 180 equal circles on a sphere. Elemente der Mathematik. Vol. 38, 1983, 119-122.
Corrections à l'article "ordres C.A.C.", Fundamenta Mathematicae 79 (1973), pp. 11-22
Corrections to my papers “Some remarks on Menger's theorem” and “Alternating connectivity of digraphs”