Results 161 to 170 of about 5,978,611 (274)

A tabu search heuristic based on k-diamonds for the weighted feedback vertex set problem

Given an undirected and vertex weighted graph G = (V,E,w), the Weighted Feedback Vertex Problem (WFVP) consists of finding a subset F ⊆ V of vertices of minimum weight such that each cycle in G contains at least one vertex in F.
Gentili, Monica, Parlato, Gennaro, Cerulli, Raffaele, Carrabs, Francesco   +3 more
core   +1 more source

Entropy and topological indices of nanostar dendrimers: a graph-theoretic approach. [PDF]

Front Chem
Nawaz A, Bokhary SAUH, Imran M.
europepmc   +1 more source

Graph Theory. 2. Vertex Descriptors and Graph Coloring

, 2002
This original work presents the construction of a set of ten sequence matrices and their applications for ordering vertices in graphs. For every sequence matrix three ordering criteria are applied: lexicographic ordering, based on strings of numbers ...
Lorentz Jäntschi
core  

Partial Steiner Triple Systems With an Almost Parallel Class Missing Any Given Point

Journal of Combinatorial Designs, EarlyView.
ABSTRACT We say that a hypergraph is factor critical if it has no 1‐factor but deletion of any vertex results in a hypergraph that has a 1‐factor. We show that any factor‐critical hypergraph of order n $n$ has at least n $n$ edges, and that for all integers k > 1 $k\gt 1$ and n > 1 $n\gt 1$ with n ≡ 1 ( mod k ) $n\equiv 1({\rm{mod}}\,k)$ there exists a
Darryn Bryant, Sara Davies, Jack Neubecker   +2 more
wiley   +1 more source

Fuzzy topological analysis of fuzzy Helm graphs with applications to protein interaction networks. [PDF]

Sci Rep
Mufti ZS, Tedjani AH, Liaqat S, Ganati GA.   +3 more
europepmc   +1 more source

Catalan Bounds for Symmetric Strength‐Two Orthogonal Arrays

Journal of Combinatorial Designs, EarlyView.
ABSTRACT A Hamming shell construction is a two‐level array obtained by taking every binary vector of a given Hamming weight a prescribed number of times, for each weight in turn. Such arrays are invariant under all permutations of the factors, and they are strength‐two orthogonal arrays exactly when the multiplicities satisfy three linear constraints ...
Ruwan C. Karunanayaka
wiley   +1 more source

Predicting properties of antifungal drug molecules using neighborhood degree topological indices. [PDF]

Sci Rep
Almulla AA, Irfan I, Mufti ZS, Almulla MO, Ganati GA.   +4 more
europepmc   +1 more source

On Odd Covers of Cliques and Disjoint Unions

Journal of Graph Theory, EarlyView.
ABSTRACT Babai and Frankl posed the “odd cover problem” of finding the minimum cardinality of a collection of complete bipartite graphs such that every edge of the complete graph of order n $n$ is covered an odd number of times. In a previous paper with O'Neill, some of the authors proved that this value is always ⌈ n / 2 ⌉ $\lceil n/2\rceil $ or ⌈ n /
Calum Buchanan, Alexander Clifton, Eric Culver, Péter Frankl, Jiaxi Nie, Kenta Ozeki, Puck Rombach, Mei Yin   +7 more
wiley   +1 more source

Independent set-based multivariate graph polynomials for fractal-type silicate triangle structures. [PDF]

Front Chem
Nithiya KS, Easwaramoorthy D.
europepmc   +1 more source

Explicit 3‐colorings for Exponential Graphs

Journal of Graph Theory, EarlyView.
ABSTRACT In 1985, El‐Zahar and Sauer showed that the chromatic number of the direct product of two 4‐chromatic graphs is 4, establishing a nontrivial case of Hedetniemi's conjecture, which has since been refuted in general. Their proof uses the concept of an exponential graph, showing that if a graph H $H$ has no proper 3‐coloring, then the exponential
Adrien Argento, Pierre Charbit, Alantha Newman   +2 more
wiley   +1 more source