Hechao Liu

most citedExtremal Kirchhoff index in polycyclic chains

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

collaborators

5 papers

math.CO2022★ 2 cited

Extremal Kirchhoff index in polycyclic chains

Hechao Liu, Lihua You

The Kirchhoff index of graphs, introduced by Klein and Randić in 1993, has been known useful in the study of computer science, complex network and quantum chemistry. The Kirchhoff…

math.GM2022

Maximum zeroth-order general Randić index of orientations of cacti

Jiaxiang Yang, Hanyuan Deng, Zikai Tang +1

The zeroth-order general Randić index $R_{a + 1}^{0}$ of an $n$ -vertices oriented graph $D$ is equal to the sum of $(d_{u_{i}}^{+})^{a} + (d_{u_{j}}^{-})^{a}$ over all arcs $u_{i} u_{j}$ of $D$ …

math.CO2022

The Sombor index and coindex of two-trees

Zenan Du, Lihua You, Hechao Liu +1

The Sombor index of a graph $G$ , introduced by Ivan Gutman, is defined as the sum of the weights $d_{G} (u)^{2} + d_{G} (v)^{2}$ of all edges $uv$ of $G$ , where $d_{G} (u)$ denotes the deg…

math.CO2021

The expected values of Sombor indices in random hexagonal chains, phenylene chains and Sombor indices of some chemical graphs

Xiaona Fang, Lihua You, Hechao Liu

Hexagonal chains are a special class of catacondensed benzenoid system and phenylene chains are a class of polycyclic aromatic compounds. Recently, A family of Sombor indices was i…

math.CO2021

Ordering chemical graphs by Sombor indices and its applications

Hechao Liu, Lihua You, Yufei Huang

Topological indices are a class of numerical invariants that predict certain physical and chemical properties of molecules. Recently, two novel topological indices, named as Sombor…