In this paper we answer a question posed [1]. We show that χ(H2m,3m+2) = m + k + 1 such that k = m/2 and H2m,3m+2 is the Harary graph. Mathematics Subject Classification: 05C15

We study an impartial game introduced by Anderson and Harary. This game is played by two players who alternately choose previously-unselected elements of a finite group. The first player who builds a generating set from the jointly-selected elements wins. We determine the nimnumbers of this game for generalized dihedral groups, which are of the form Dih(A) = Z2 n A for a finite abelian group A.

We determine the minimum size of n-factor-critical graphs and that of k-extendable bipartite graphs, by considering Harary graphs and related graphs. Moreover, we determine the minimum size of k-extendable non-bipartite graphs for k = 1, 2, and pose a related conjecture for general k.

the topological indices, defined as the sum of contributions of all pairs of vertices (among which are the wiener, harary, hyper–wiener indices, degree distance, and many others), are expressed in terms of contributions of edges and pairs of edges.

The diameter of a graph is an important factor for communication as it determines the maximum communication delay between any pair of processors in a network. Graham and Harary [N. Graham, F. Harary, Changing and unchanging the diameter of a hypercube, Discrete Applied Mathematics 37/38 (1992) 265–274] studied how the diameter of hypercubes can be affected by increasing and decreasing edges. Th...

Mosquitoes are a great threat to human health date and subject of interdisciplinary research involving scientists from many areas. Recently much attention has been put novel approaches mosquito repellent products that involve the use materials, such as carbon nanomaterials, where it is essential determine their properties. This discusses full molecular characterization nanotubes (CNTs) produced...

The Harary-Hill conjecture states that for every n > 0 the complete graph on n vertices Kn, the minimum number of crossings over all its possible drawings equals H(n) := 1 4 ⌊n 2 ⌋⌊n− 1 2 ⌋⌊n− 2 2 ⌋⌊n− 3 2 ⌋ . So far, the lower bound of the conjecture could only be verified for arbitrary drawings of Kn with n ≤ 12. In recent years, progress has been made in verifying the conjecture for certain ...