On -edge cover coloring of nearly bipartite graphs.
On Finite Groups Generated by Odd Transpositions. I.
On finite homomorphic images of the multiplicative group of a division algebra.
On Graphical Regular Representations of Direct Products of Groups.
On infinite tournaments with regular automorphism groups.
On iteration digraph and zero-divisor graph of the ring
In the first part, we assign to each positive integer a digraph whose set of vertices consists of elements of the ring with the addition and the multiplication operations modulo and for which there is a directed edge from to if and only if . Associated with are two disjoint subdigraphs: and whose union is The vertices of are coprime to and the vertices of are not coprime to In this part, we study the structure of in detail. In the second part, we investigate the zero-divisor...
On -walk-regular graphs.
On L-ideal-based L-zero-divisor graphs
In a manner analogous to a commutative ring, the L-ideal-based L-zero-divisor graph of a commutative ring R can be defined as the undirected graph Γ(μ) for some L-ideal μ of R. The basic properties and possible structures of the graph Γ(μ) are studied.
On line-symmetric graphs
On linguistic dynamical systems, families of graphs of large girth, and cryptography.
On mapping graphs and permutation graphs
On minimal semirigid relations
On permutographs
On Principal Graphs and Weak Duality.
On rank 2 geometries of the Mathieu group .
On rational radii coin representations of the wheel graph
A flower is a coin graph representation of the wheel graph. A petal of a flower is an outer coin connected to the center coin. The results of this paper are twofold. First we derive a parametrization of all the rational (and hence integer) radii coins of the 3-petal flower, also known as Apollonian circles or Soddy circles. Secondly we consider a general n-petal flower and show there is a unique irreducible polynomial Pₙ in n variables over the rationals ℚ, the affine variety of which contains the...
On semiregular digraphs of the congruence
We assign to each pair of positive integers and a digraph whose set of vertices is and for which there is a directed edge from to if . The digraph is semiregular if there exists a positive integer such that each vertex of the digraph has indegree or 0. Generalizing earlier results of the authors for the case in which , we characterize all semiregular digraphs when is arbitrary.
On some characterizations of strong power graphs of finite groups
Let G be a finite group of order n. The strong power graph Ps(G) of G is the undirected graph whose vertices are the elements of G such that two distinct vertices a and b are adjacent if am1=bm2 for some positive integers m1, m2 < n. In this article we classify all groups G for which Ps(G) is a line graph. Spectrum and permanent of the Laplacian matrix of the strong power graph Ps(G) are found for any finite group G.
On some systems of equations with constraints in a free group. – Addenda. (Sur certains systèmes d'équations avec constraintes dans un groupe libre. – Addenda.)
On some systems of equations with constraints in a free group. (Sur certains systèmes d'équations avec contraintes dans un groupe libre.)