activity
20142026
most citedAnti-Ramsey numbers of graphs with some decomposition family sequences

5 citations · 18 across the 23 of their papers we have counts for

collaborators

25 papers

math.CO2026

Turán numbers of triangular pyramids

Chuanqi Xiao, Long-Tu Yuan, Xiaowen Zhang

Let $\TP_k$ denote the triangular pyramid with layers. For a graph family , let $\ex(n,\mathcal F)$ be the maximum number of edges in an -vertex graph containing…

math.CO2026

Exact generalized Turán number of vertex-disjoint paths of length two

Qi Wu, Long-Tu Yuan

We determine the generalized Turán number of vertex-disjoint paths of length two and characterize all corresponding extremal graphs. Our proof combines the Lovász form of the Krusk…

math.CO2026

Strong counterexamples to a supersaturation question of Ma-Yuan

Wanfang Chen, Long-Tu Yuan

For a graph , let be the minimum number of copies of in an -vertex graph with edges, where is the maximum number of edg…

math.CO2026

Triangles in graphs without the expansion of -cycle

Jialei Song, Qi Wu, Long-Tu Yuan

The expansion of a graph is the graph obtained from by replacing each edge with a triangle. Lv \etal proposed a conjecture on the maximum number of triangle…

math.CO2026

Anti-Ramsey numbers for cancellative configurations in p-graphs

Cheng Chi, Long-tu Yuan

We study edge-colorings of the complete -graph on vertices that contain no three edges of distinct colors such that the symmetric difference of and is contai…

math.CO2025

Exact Turán numbers of two vertex-disjoint paths

Miao Dong, Bo Ning, Long-Tu Yuan +1

The Turán number of a graph is the maximum number of edges in any graph of order that does not contain as a subgraph. In 1959, Erd\H os and Gallai obtained a sharp uppe…

math.CO2024

Spectral radius and the 2-power of Hamilton paths

Te Pi, Rui Sun, Long-Tu Yuan

We determine the maximum number of a graph without containing the 2-power of a Hamilton path. Using this result, we establish a spectral condition for a graph containing the 2-powe…

math.CO2023

Supersaturation beyond color-critical graphs

Jie Ma, Long-Tu Yuan

The supersaturation problem for a given graph asks for the minimum number of copies of in an -vertex graph with edges. Subsequent works by Rademac…

math.CO2023★ 2 cited

Exact results for some extremal problems on expansions I

Xizhi Liu, Jialei Song, Long-Tu Yuan

The expansion of a graph , denoted by , is the -graph obtained from by adding a new vertex to each edge such that different edges receive different vertices. For lar…

math.CO2023★ 1 cited

A step towards a general density Corrádi--Hajnal Theorem

Jianfeng Hou, Heng Li, Xizhi Liu +2

For a nondegenerate -graph , large , and in the regime , where is a constant depending only on , we present a general approach for determining…

math.CO2022

A stability theorem for multi-partite graphs

Wanfang Chen, Changhong Lu, Long-Tu Yuan

The Erdős-Simonovits stability theorem is one of the most widely used theorems in extremal graph theory. We obtain an Erdős-Simonovits type stability theorem in multi-partite graph…

math.CO2022★ 1 cited

Stability in Bondy's theorem on paths and cycles

Bo Ning, Long-tu Yuan

In this paper, we study the stability result of a well-known theorem of Bondy. We prove that for any 2-connected non-hamiltonian graph, if every vertex except for at most one verte…

math.CO2022

The Turán number for the edge blow-up of trees: the missing case

Cheng Chi, Long-Tu Yuan

The edge blow-up of a graph is the graph obtained from replacing each edge of it by a clique of the same size where the new vertices of the cliques are all different. Wang, Hou, Li…

math.CO2022

The bipartite Turan number and spectral extremum for linear forests

Ming-Zhu Chen, Ning Wang, Long-Tu Yuan +1

The bipartite Turán number of a graph , denoted by , is the maximum number of edges in any bipartite graph with and which does not conta…

math.CO2021★ 4 cited

Anti-Ramsey numbers for paths

Long-Tu Yuan

We determine the anti-Ramsey numbers for paths. This confirms a conjecture posed by Erdős, Simonovits and Sós in 1970s.

math.CO2020

A clique version of the Erdős-Gallai stability theorems

Jie Ma, Long-Tu Yuan

Combining Pósa's rotation lemma with a technique of Kopylov in a novel approach, we prove a generalization of the Erdős-Gallai theorems on cycles and paths. This implies a clique v…

math.CO2020

Extremal graphs of the -th power of paths

Long-Tu Yuan

An extremal graph for a given graph is a graph with maximum number of edges on fixed number of vertices without containing a copy of . The -th power of a path is a graph…

math.CO2020

On the anti-Ramsey numbers of linear forests

Tian-Ying Xie, Long-Tu Yuan

For a fixed graph , the , , is the maximum number of colors in an edge-coloring of which does not contain a rainbow copy of . In t…

math.CO2020★ 4 cited

Extremal graphs for wheels

Long-Tu Yuan

For a graph , the Turán number of , denoted by ex, is the maximum number of edges of an -vertex -free graph. Let denote the maximum number of edges not…

math.CO2019

Extremal graphs for edge blow-up of graphs

Long-Tu Yuan

Given a graph and an integer , the {\it edge blow-up} of , denoted as , is the graph obtained from replacing each edge in by a clique of size where the…

math.CO2019★ 5 cited

Anti-Ramsey numbers of graphs with some decomposition family sequences

Long-Tu Yuan, Xiao-Dong Zhang

For a given graph , the anti-Ramsey number of is the maximum number of colors in an edge-coloring of a complete graph which does not contain a rainbow copy of . In this p…

math.CO2017

A Variation of the Erdős-Sós Conjecture in Bipartite Graphs

Long-Tu Yuan, Xiao-Dong Zhang

The Erdős-Sós Conjecture states that every graph with average degree more than contains all trees of order as subgraphs. In this paper, we consider a variation of the abo…

math.CO2016★ 1 cited

Turán numbers for disjoint paths

Long-Tu Yuan, Xiao-Dong Zhang

The Turán number of a graph , , is the maximum number of edges in any graph of order which does not contain as a subgraph. Lidický, Liu and Palmer determined $e…

math.CO2015

The Turan Number of Disjoint Copies of Paths

Long-Tu Yuan, Xiao-Dong Zhang

The Turán number of a graph , , is the maximum number of edges in a simple graph of order which does not contain as a subgraph. Let denote disj…