Zilong Yan

collaborators

3 papers

math.CO2021

Tree Embeddings and Tree-Star Ramsey Numbers

Zilong Yan, Yuejian Peng

We say that a graph $F$ can be embedded into a graph $G$ if $G$ contains an isomorphic copy of $F$ as a subgraph. Guo and Volkmann \cite{GV} conjectured that if $G$ is a connected…

math.CO2021

Non-jumping Turán densities of hypergraphs

Zilong Yan, Yuejian Peng

A real number $α \in [0, 1)$ is a jump for an integer $r \geq 2$ if there exists $c > 0$ such that no number in $(α, α + c)$ can be the Turán density of a family of $r$ -uniform graphs. A…

math.CO2021

An irrational Lagrangian density of a single hypergraph

Zilong Yan, Yuejian Peng

The {\em Turán number} of an $r$ -uniform graph $F$ , denoted by $e x (n, F)$ , is the maximum number of edges in an $F$ -free $r$ -uniform graph on $n$ vertices. The {\em Turán density} o…