-
421
Structure and enumeration of $(3+1)$-free posets (extended abstract)
Published 2013-01-01“…We enumerate all $(3+1)$-free posets by giving a decomposition into bipartite graphs, and obtain generating functions for $(3+1)$-free posets with labelled or unlabelled vertices.…”
Get full text
Article -
422
Topological network entanglement as order parameter for the emergence of geometry
Published 2017-01-01“…As a concrete example we analyze the recently proposed model in which geometry emerges due to the condensation of 4-cycles in random regular bipartite graphs, driven by the combinatorial Ollivier–Ricci curvature. …”
Get full text
Article -
423
Edge-maximal -free non-bipartite Hamiltonian graphs of odd order
Published 2022-09-01“…AbstractLet [Formula: see text] denote the class of non-bipartite graphs on n vertices containing no [Formula: see text]-graph and [Formula: see text] Let [Formula: see text] denote the class of non-bipartite Hamiltonian graphs on n vertices containing no [Formula: see text]-graph and [Formula: see text] In this paper we determine [Formula: see text] by proving that for sufficiently large odd n, [Formula: see text] Furthermore, the bound is best possible. …”
Get full text
Article -
424
A fast new algorithm for weak graph regularity
Published 2020“…The algorithm outputs an approximation of a given graph as a weighted sum of ϵ-O(1) many complete bipartite graphs. As a corollary, we give a deterministic algorithm for estimating the number of copies of H in an n-vertex graph G up to an additive error of at most ϵn v(H), in time ϵ-O H(1) n 2…”
Get full text
Article -
425
Tilings of a Domain on a Hexagon Mesh with Balanced 3-Tiles
Published 2001-01-01“…The first one is based on matchings in bipartite graphs, which in this case are in correspondance with tilings of domains by lozenges, and thus can be efficiently studied, using Thurston's algorithm (see [Thu90]). …”
Get full text
Article -
426
Optimal quantization for compressive sensing under message passing reconstruction
Published 2012“…GAMP is an iterative reconstruction scheme inspired by the belief propagation algorithm on bipartite graphs which generalizes approximate message passing (AMP) for arbitrary measurement channels. …”
Get full text
Article -
427
The Distance Magic Index of a Graph
Published 2018-02-01“…In this paper we determine the distance magic index of trees and complete bipartite graphs.…”
Get full text
Article -
428
Gaussian Amplitude Amplification for Quantum Pathfinding
Published 2022-07-01“…We focus on the geometry of sequentially connected bipartite graphs, which naturally gives rise to solution spaces describable by Gaussian distributions. …”
Get full text
Article -
429
Approximating partition functions of bounded-degree Boolean counting Constraint Satisfaction Problems
Published 2020“…Our main result shows that: (i) if every function in Γ is affine, then #CSP∆(Γ) is in FP for all ∆, (ii) otherwise, if every function in Γ is in a class called IM2, then for large ∆, #CSP∆(Γ) is equivalent under approximation-preserving reductions to the problem of counting independent sets in bipartite graphs, (iii) otherwise, for large ∆, it is NP-hard to approximate #CSP∆(Γ), even within an exponential factor.…”
Journal article -
430
Finding Dominating Induced Matchings in P9-Free Graphs in Polynomial Time
Published 2022-11-01“…The DIM problem is -complete even for very restricted graph classes such as planar bipartite graphs with maximum degree 3 but was solved in linear time for P7-free graphs and in polynomial time for P8-free graphs. …”
Get full text
Article -
431
Approximately counting locally-optimal structures
Published 2016“…Assuming that #BIS is not equivalent to #SAT under AP-reductions, we show that counting maximal independent sets in bipartite graphs is harder than counting maximum independent sets. …”
Journal article -
432
Annihilating Graph of Abelian Groups
Published 2021-12-01“…Among other things, we characterize Abelian groups for which their annihilating graphs are complete, bipartite or complete bipartite graphs.…”
Get full text
Article -
433
A new two-variable generalization of the chromatic polynomial
Published 2003-01-01“…We finally give explicit expressions for the generalized chromatic polynomial of complete graphs, complete bipartite graphs, paths, and cycles, and show that it can be computed in polynomial time for trees and graphs of restricted pathwidth.…”
Get full text
Article -
434
On interval number in cycle convexity
Published 2018-05-01“…Then, we present some hardness results by showing that deciding whether $in_{cc} (G)$ ≤ k is NP-complete, even if G is a split graph or a bounded-degree planar graph, and that the problem is W[2]-hard in bipartite graphs when k is the parameter. As a consequence, we obtainthat $in_{cc} (G)$ cannot be approximated up to a constant factor in the classes of split graphs and bipartite graphs (unless P = N P ).On the positive side, we present polynomial-time algorithms to compute $in_{cc} (G)$ for outerplanar graphs, cobipartite graphs and interval graphs. …”
Get full text
Article -
435
Five results on maximizing topological indices in graphs
Published 2021-11-01“…We prove that the maximum for the difference of the Wiener index and the eccentricity is attained by the path if the order $n$ is at least $9$ and that the maximum weighted Szeged index of graphs of given order is attained by the balanced complete bipartite graphs.…”
Get full text
Article -
436
Modeling Information Flow in Face-to-Face Meetings while Protecting Privacy
Published 2005“…Rather than looking at graphs derived from email, on-line forums, or telephone connections, we consider sequences of bipartite graphs that represent face-to-face meetings between individuals, and define a new metric to identify the information elite individuals. …”
Get full text
Article -
437
On the relationship between variable Wiener index and variable Szeged index
Published 2022“…They proved the weak conjecture for bipartite graphs, and the strong conjecture for trees. …”
Journal article -
438
Pattern-Avoidance in Binary Fillings of Grid Shapes (short version)
Published 2008-01-01“…For some shapes, fillings that avoid specific $2 \times 2$ pairs are in bijection with totally nonnegative Grassmann cells, or with acyclic orientations of bipartite graphs. We prove a number of results analogous to Wilf-equivalence for these objects ―- that is, we show that for certain classes of shapes, some pattern-avoiding fillings are equinumerous with others.…”
Get full text
Article -
439
Research of NP-Complete Problems in the Class of Prefractal Graphs
Published 2021-10-01“…As an example, algorithms for searching for spanning trees and packing bipartite graphs are proposed. The developed algorithms are polynomial and based on well-known algorithms and are used in the form of procedures. …”
Get full text
Article -
440
On Eccentricity Version of Zagreb Coindices
Published 2021-06-01“…We also determine the extremal values of the second Zagreb eccentricity coindex over some specific families of graphs such as trees, unicyclic graphs, connected graphs, and connected bipartite graphs and describe the extremal graphs. Moreover, we compare the second Zagreb eccentricity coindex with the eccentric connectivity coindex and give directions for further studies.…”
Get full text
Article