Zhiyu Wang

collaborators

3 papers

math.CO2025

On the smallest eigenvalues of $3$ -colorable graphs

Zilin Jiang, Zhiyu Wang

We prove that the set of the smallest eigenvalues attained by $3$ -colorable graphs is dense in $(- \infty, - I^»^{*})$ , where $I^»^{*} = I ¨ ^{1/2} + I ¨ ^{- 1/2} \approx 2.01980$ and $I ¨ $ is t…

math.CO2025

Counting $k$ -cycles in $5$ -connected planar triangulations

Gyaneshwar Agrahari, Xiaonan Liu, Zhiyu Wang

We show that every $n$ -vertex $5$ -connected planar triangulation has at most $9 n - 50$ many cycles of length $5$ for all $n \geq 20$ and this upper bound is tight. We also show that fo…

math.CO2025

On the oriented diameter of graphs with given minimum degree

Garner Cochran, Zhiyu Wang

ErdÅs, Pach, Pollack, and Tuza [\textit{J. Combin. Theory Ser. B, 47(1) (1989), 73-79}] proved that the diameter of a connected $n$ -vertex graph with minimum degree $I^´$ is at mos…

On the smallest eigenvalues of 3-colorable graphs

Counting k-cycles in 5-connected planar triangulations

On the oriented diameter of graphs with given minimum degree

On the smallest eigenvalues of $3$ -colorable graphs

Counting $k$ -cycles in $5$ -connected planar triangulations