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The paraphrase identification task involves measuring semantic similarity between two short sentences. It is a tricky task, and multilingual paraphrase identification is even more challenging. In this work, we train a bi-encoder model in a…

Computation and Language · Computer Science 2024-06-24 Inessa Fedorova , Aleksei Musatow

We characterize the graphs for which the independence number equals the packing number. As a consequence we obtain simple structural descriptions of the graphs for which (i) the distance-$k$-packing number equals the distance-$2k$-packing…

Combinatorics · Mathematics 2014-02-26 Felix Joos , Dieter Rautenbach

We show that computing the interleaving distance between two multi-graded persistence modules is NP-hard. More precisely, we show that deciding whether two modules are $1$-interleaved is NP-complete, already for bigraded, interval…

Computational Geometry · Computer Science 2019-10-10 Håvard Bakke Bjerkevik , Magnus Bakke Botnan , Michael Kerber

Maximum-likelihood decoding is one of the central algorithmic problems in coding theory. It has been known for over 25 years that maximum-likelihood decoding of general linear codes is NP-hard. Nevertheless, it was so far unknown whether…

Computational Complexity · Computer Science 2007-07-16 Venkatesan Guruswami , Alexander Vardy

We study the consensus-halving problem of dividing an object into two portions, such that each of $n$ agents has equal valuation for the two portions. The $\epsilon$-approximate consensus-halving problem allows each agent to have an…

Computer Science and Game Theory · Computer Science 2018-08-09 Aris Filos-Ratsikas , Soren Kristoffer Stiil Frederiksen , Paul W. Goldberg , Jie Zhang

The scramble number of a graph is an invariant recently developed to aid in the study of divisorial gonality. In this paper we prove that scramble number is NP-hard to compute, also providing a proof that computing gonality is NP-hard even…

Combinatorics · Mathematics 2021-12-09 Marino Echavarria , Max Everett , Robin Huang , Liza Jacoby , Ralph Morrison , Ben Weber

A graph is called $t$-tough if the removal of any vertex set $S$ that disconnects the graph leaves at most $|S|/t$ components. The toughness of a graph is the largest $t$ for which the graph is $t$-tough. A graph is minimally $t$-tough if…

Discrete Mathematics · Computer Science 2022-09-02 Gyula Y Katona , István Kovács , Kitti Varga

Link prediction methods use patterns in known network data to infer which connections may be missing. Previous work has shown that continuous-time quantum walks can be used to represent path-based link prediction, which we further study…

Quantum Physics · Physics 2022-12-01 João P. Moutinho , Duarte Magano , Bruno Coutinho

It is proved that the rectilinear crossing number of every graph with bounded tree-width and bounded degree is linear in the number of vertices. **** This paper has been withdrawn by the author. **** The results have been superseeded by the…

Combinatorics · Mathematics 2007-05-23 David R. Wood

The crossing number of a graph is the minimum number of crossings over all of its drawings on the plane. The Crossing Lemma, proved more than 40 years ago, is a tight lower bound on the crossing number of a graph in terms of the number of…

Combinatorics · Mathematics 2025-09-18 Geza Toth

In this paper we investigate formal verification problems for Neural Network computations. Various reachability problems will be in the focus, such as: Given symbolic specifications of allowed inputs and outputs in form of Linear…

Computational Complexity · Computer Science 2023-06-12 Adrian Wurm

Trivial links are unique up to number of link components, but they can be hard to recognize from arbitrary diagrams. We define a new measure of the complexity of a link embedding, the crumple, and show how this may be used to measure…

Geometric Topology · Mathematics 2013-02-28 Chad Musick

We show that the problem of counting perfect matchings remains #P-complete even if we restrict the input to very dense graphs, proving the conjecture in [5]. Here "dense graphs" refer to bipartite graphs of bipartite independence number…

Data Structures and Algorithms · Computer Science 2022-10-28 Nicolas El Maalouly , Yanheng Wang

We introduce the Orchard crossing number, which is defined in a similar way to the well-known rectilinear crossing number. We compute the Orchard crossing number for some simple families of graphs. We also prove some properties of this…

Combinatorics · Mathematics 2009-04-23 Elie Feder , David Garber

Deciding whether a graph can be embedded in a grid using only unit-length edges is NP-complete, even when restricted to binary trees. However, it is not difficult to devise a number of graph classes for which the problem is polynomial, even…

Data Structures and Algorithms · Computer Science 2012-04-13 Vinícius G. P. de Sá , Guilherme D. da Fonseca , Raphael Machado , Celina M. H. de Figueiredo

We address the question of detecting minimal virtual diagrams with respect to the number of virtual crossings. This problem is closely connected to the problem of detecting the minimal number of additional intersection points for a generic…

Geometric Topology · Mathematics 2008-11-06 Denis Afanasiev , Vassily Manturov

In multistage perfect matching problems we are given a sequence of graphs on the same vertex set and asked to find a sequence of perfect matchings, corresponding to the sequence of graphs, such that consecutive matchings are as similar as…

Data Structures and Algorithms · Computer Science 2021-05-11 Markus Chimani , Niklas Troost , Tilo Wiedera

We define the crosscap number of a 2-component link as the minimum of the first Betti numbers of connected, non-orientable surfaces bounding the link. We discuss some properties of the crosscap numbers of 2-component links.

Geometric Topology · Mathematics 2007-05-23 Gengyu Zhang

We give a proof for sharp estimate for the number of spanning trees using linear algebra and generalize this bound to multigraphs. In addition, we show that this bound is tight for complete graphs. In addition, we give estimates for number…

Combinatorics · Mathematics 2022-12-01 K. V. Chelpanov

In this paper, we define a lassoing on a link, a local addition of a trivial knot to a link. Let K be an s-component link with the Conway polynomial non-zero. Let L be a link which is obtained from K by r-iterated lassoings. The complete…

Geometric Topology · Mathematics 2011-01-04 Ayaka Shimizu