Zhenhua Lyu

activity

20162026

most citedExtremal digraphs avoiding an orientation of

C_{4}

2 citations · 3 across the 9 of their papers we have counts for

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math.CO2018

0-1 matrices with zero trace whose squares are 0-1 matrices

Zejun Huang, Zhenhua Lyu

In this paper, we determine the maximum number of nonzero entries in 0-1 matrices of order $n$ with zero trace whose squares are 0-1 matrices when $n \geq 8$ . The extremal matrices a…

math.CO2018★ 2 cited

Extremal digraphs avoiding an orientation of $C_{4}$

Zejun Huang, Zhenhua Lyu

Let $P_{2, 2}$ be the orientation of $C_{4}$ which consists of two 2-paths with the same initial and terminal vertices. In this paper, we determine the maximum size of $P_{2, 2}$ -free…

0-1 matrices with zero trace whose squares are 0-1 matrices

Extremal digraphs avoiding an orientation of C4​

Extremal digraphs avoiding an orientation of $C_{4}$