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20222026
most citedDetermining the minimum size of maximal 1-plane graphs

1 citations · 1 across the 14 of their papers we have counts for

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14 papers

math.CO2026

On the Restricted Edge-Cuts of Optimal 1-Planar Graphs

Licheng Zhang, Zhangdong Ouyang, Yuanqiu Huang +1

The restricted edge-connectivity of a graph is the minimum size of an edge-cut whose removal leaves every component with at least two vertices. In 2024, Zhang et al. showed that th…

math.CO2026

The maximum number of -cliques of 7-connected 1-planar graphs

Yuanqiu Huang, Licheng Zhang

In 2023, Gollin, Hendrey, Methuku, Tompkins and Zhang determined the maximum number of cliques in general 1-planar graphs with order . Their extremal examples have connectivity…

math.CO2026

Extremal 1-planar graphs without k-cliques

Licheng Zhang, Yuanqiu Huang, Fengming Dong

In 2016, Dowden initiated the study of planar Turán-type problems, which has since attracted considerable attention. Recently, Bekos et al. proved that every -free -planar…

math.CO2025

A note on optimal 2-planar graphs

Licheng Zhang, Yuanqiu Huang, Zhangdong Ouyang

In this note, we prove that every 4-connected optimal 2-planar graph is Hamiltonian-connected. Furthermore, we show that the 4-connectedness condition is sharp by constructing infi…

math.CO2025

Maximal 1-plane graphs with the maximum number of crossings

Zhangdong Ouyang, Yuanqiu Huang, Licheng Zhang

A drawing of a graph in the plane is called 1-planar if each edge is crossed at most once. A graph together with a 1-planar drawing is a 1-plane graph. A 1-plane graph with exa…

math.CO2025

The minimum size of maximal bipartite IC-plane graphs with given connectivity

Guiping Wang, Yuanqiu Huang, Zhangdong Ouyang +1

Recently, the problem of establishing bounds on the edge density of 1-planar graphs, including their subclass IC-planar graphs, has received considerable attention. In 2018, Angeli…

math.CO2025

The minimum crossing number and minimum size of maximal 1-plane graphs with given connectivity

Zhangdong Ouyang, Yuanqiu Huang, Licheng Zhang +1

A 1-planar graph is a graph which has a drawing on the plane such that each edge is crossed at most once. If a 1-planar graph is drawn in that way, the drawing is called a {\it 1-p…

math.CO2025★ 1 cited

Determining the minimum size of maximal 1-plane graphs

Yuanqiu Huang, Zhangdong Ouyang, Licheng Zhang +1

A 1-plane graph is a graph together with a drawing in the plane in such a way that each edge is crossed at most once. A 1-plane graph is maximal if no edge can be added without vio…

math.CO2025

The sharp upper bounds on the maximum degree and vertex-connectivity of claw-free 1-planar graphs

Licheng Zhang, Zhangdong Ouyang, Yuanqiu Huang

The complete bipartite graph is called a claw. The properties of claw-free graphs have attracted considerable attention, with research on claw-free planar graphs tracing…

math.CO2024

Two classes of connectivity-related non-Hamiltonian 1-planar perfect graphs

Licheng Zhang, Shengxiang Lv, Yuanqiu Huang

The existence of Hamiltonian cycles in 1-planar graphs with higher connectivity has attracted considerable attention. Recently, the authors and Dong proved that 4-connected 1-plana…

math.CO2024

The minimum size of 2-connected chordal bipartite graphs

Licheng Zhang, Yuanqiu Huang

A bipartite graph is chordal bipartite if every cycle of length at least six contains a chord. We determine the minimum size in 2-connected chordal bipartite graphs with given orde…

math.CO2024

4-connected 1-planar chordal graphs are Hamiltonian-connected

Licheng Zhang, Yuanqiu Huang, Shengxiang Lv +1

Tutte proved that 4-connected planar graphs are Hamiltonian. It is unknown if there is an analogous result on 1-planar graphs. In this paper, we characterize 4-connected 1-planar c…

math.CO2023

On the sizes of generalized cactus graphs

Licheng Zhang, Yuanqiu Huang

A cactus is a connected graph in which each edge is contained in at most one cycle. We generalize the concept of cactus graphs, i.e., a -cactus is a connected graph in which eac…

math.CO2022

The reducibility of optimal 1-planar graphs

Licheng Zhang, Yuanqiu Huang

A graph is reducible if it is the lexicographic product of two smaller non-trivial graphs. It is well-known a 1-planar graph with vertices has at most edges, and…