Vacca-type series for values of the generalized Euler constant function and its derivative.
Valency seven symmetric graphs of order
A graph is said to be symmetric if its automorphism group acts transitively on its arcs. In this paper, all connected valency seven symmetric graphs of order are classified, where , are distinct primes. It follows from the classification that there is a unique connected valency seven symmetric graph of order , and that for odd primes and , there is an infinite family of connected valency seven one-regular graphs of order with solvable automorphism groups, and there are four sporadic ones...
Validity of the weakened Hadwiger hypothesis
Validity up to complementation in graph theory
Valuated matroids---a new look at the greedy algorithm.
Valuations and Möbius Function.
Value sets of graphs edge-weighted with elements of a finite abelian group
Given a graph G = (V,E) of order n and a finite abelian group H = (H,+) of order n, a bijection f of V onto H is called a vertex H-labeling of G. Let g(e) ≡ (f(u)+f(v)) mod H for each edge e = u,v in E induce an edge H-labeling of G. Then, the sum is called the H-value of G relative to f and the set HvalS(G) of all H-values of G over all possible vertex H-labelings is called the H-value set of G. Theorems determining HvalS(G) for given H and G are obtained.
Value-peaks of permutations.
Values of domination numbers of the queen's graph.
Value-True Walks in Finite, Connected, Valuated Graphs.
Van der Waerden theorem for sequences of integers not containing an arithmetic progression of terms
Van der Waerden's theorem and avoidability in words.
Van der Waerden/Schrijver-Valiant like conjectures and stable (aka hyperbolic) homogeneous polynomials: one theorem for all.
Vapnik-Chervonenkis Dimension and (Pseudo-)Hyperplane Arrangements.
Variable neighborhood search for extremal graphs. 17. Further conjectures and results about the index
The AutoGraphiX 2 system is used to compare the index of a connected graph G with a number of other graph theoretical invariants, i.e., chromatic number, maximum, minimum and average degree, diameter, radius, average distance, independence and domination numbers. In each case, best possible lower and upper bounds, in terms of the order of G, are sought for sums, differences, ratios and products of the index and another invariant. There are 72 cases altogether: in 7 cases known results were reproduced,...
Variation on a theme of MacDonald.
Variations for spanning trees.
Variations on a sufficient condition for Hamiltonian graphs
Given a 2-connected graph G on n vertices, let G* be its partially square graph, obtained by adding edges uv whenever the vertices u,v have a common neighbor x satisfying the condition , where . In particular, this condition is satisfied if x does not center a claw (an induced ). Clearly G ⊆ G* ⊆ G², where G² is the square of G. For any independent triple X = x,y,z we define σ̅(X) = d(x) + d(y) + d(z) - |N(x) ∩ N(y) ∩ N(z)|. Flandrin et al. proved that a 2-connected graph G is hamiltonian if...
Variations on descents and inversions in permutations.
Variations on seven points: An introduction to the scope and methods of coding theory and finite geometries.