activity
20242026
collaborators

9 papers

math.CO2026

Treewidth of the toroidal grid

Tatsuya Gima, Hiraku Morimoto, Yuto Okada +1

In this paper, we show that the treewidth of the toroidal grid is for all . This closes the gap between the previously known upper bound of (Ell…

cs.DS2025

Forcing a unique minimum spanning tree and a unique shortest path

Tatsuya Gima, Andreas Grigorjew, Yasuaki Kobayashi +8

A forcing set in a combinatorial problem is a set of elements such that there is a unique solution that contains all the elements in . An anti-forcing set is the symmetric c…

cs.DS2025

Hitting Geodesic Intervals in Structurally Restricted Graphs

Tatsuya Gima, Yasuaki Kobayashi, Yuto Okada +2

Given a graph , a set of vertex pairs, and an integer , Hitting Geodesic Intervals asks whether there is a set of size at most such that for e…

cs.DS2025

Structural Parameterizations of -Planarity

Tatsuya Gima, Yasuaki Kobayashi, Yuto Okada

The concept of -planarity is extensively studied in the context of Beyond Planarity. A graph is -planar if it admits a drawing in the plane in which each edge is crossed at m…

cs.DS2025

Courcelle's Theorem for Lipschitz Continuity

Tatsuya Gima, Soh Kumabe, Yuichi Yoshida

Lipschitz continuity of algorithms, introduced by Kumabe and Yoshida (FOCS'23), measures the stability of an algorithm against small input perturbations. Algorithms with small Lips…

cs.DS2025

Bandwidth Parameterized by Cluster Vertex Deletion Number

Tatsuya Gima, Eun Jung Kim, Noleen Köhler +2

Given a graph and an integer , Bandwidth asks whether there exists a bijection from to such that $\max_{\{u, v \} \in E(G)} | π(u) - π(…