Jiaxiang Yang

collaborators

4 papers

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.CO2021

Maximum zeroth-order general Randić index of orientations of trees, unicyclic and bicyclic graphs with given matching number

Jiaxiang Yang, Hanyuan Deng

The zeroth-order general Randić index $R_{a}^{0}$ of a digraph $D$ is the sum of $(d_{v}^{+})^{a} + (d_{w}^{-})^{a}$ over all arcs $v w$ of $D$ , where $a$ , $d_{v}^{+}$ and $d_{w}^{-}$ …

math.CO2021

Maximum first Zagreb index of orientations of unicyclic graphs with given matching number

Jiaxiang Yang, Hanyuan Deng

Let $D = (V, A)$ be a digraphs without isolated vertices. The first Zagreb index of a digraph $D$ defined as a summation over all arcs, $M_1(D)=\frac{1}{2}\sum\limits_{uv\in A}(d^{+}_…

math.CO2021

On the vertex-degree based invariants of digraphs

Hanyuan Deng, Jiaxiang Yang, Zikai Tang +2

Let $D = (V, A)$ be a digraphs without isolated vertices. A vertex-degree based invariant $I (D)$ related to a real function $φ$ of $D$ is defined as a summation over all arcs, $I(D) =…