Joyentanuj Das

activity

20192026

most citedCounterexample to the Bougard-Joret Conjecture

5 citations · 5 across the 18 of their papers we have counts for

collaborators

21 papers

math.CO2026★ 5 cited

Counterexample to the Bougard-Joret Conjecture

Joyentanuj Das, Sayan Gupta

For admissible integers $n, α, k$ , let $f (n, α, k)$ be the minimum number of edges in a $k$ -connected graph of order $n$ and independence number $α$ . A conjecture of Bougard and Joret…

math.CO2026

A higher-connectivity spectral Ore theorem for triangle-free graphs

Joyentanuj Das, Sayan Gupta

Let $B_{n, k}$ be the graph obtained from the balanced complete bipartite graph on $n$ vertices by deleting a matching of size $k$ . If $G$ is an $n$ -vertex triangle-free graph with…

math.CO2026

A sharp fixed-size spectral bound for $k K_{3}$ -free graphs

Joyentanuj Das, Yamini V

For a fixed integer $k \geq 2$ , we establish a sharp adjacency-spectral upper bound for sufficiently large $m$ -edge $k K_{3}$ -free graphs. We prove \[ λ(G)\le (k-1)+\sqrt{m-k(k-1)}. \] M…

math.CO2026

Laplacian Bounds for the Dissociation Number of Regular Graphs of Matrix Rings

Joyentanuj Das

Let $Γ_{n} (q)$ be the graph whose vertices are the invertible matrices in $\Mat_n(\F_q)$, with two distinct matrices adjacent whenever their sum is singular. A dissociation set is a…

math.CO2026

On the minimum spectral radius of unicyclic graphs with a given matching number

Joyentanuj Das, Debabrota Mondal

A matching $M$ in a graph $G = (V, E)$ is a set of edges such that no two edges in $M$ share a common vertex. A matching with maximum cardinality is called a maximum matching and i…

math.CO2025

The exponential distance matrix of bi-block graphs

Joyentanuj Das, Sumit Mohanty

Let $G$ be a connected graph with vertex set ${v_{1}, v_{2}, \dots, v_{n}}$ . As a variant of the classical distance matrix, the \emph{exponential distance matrix} was introdu…

math.CO2025

A $q$ -analogue of distance matrix of bi-block graphs

Joyentanuj Das

A $q$ -analogue of the distance matrix, referred to as the \emph{ $q$ -distance matrix}, is obtained from the distance matrix by replacing each nonzero entry $α$ with the sum $1+q+\cd…

math.CO2025

On the Squared Distance Matrix of a Starlike Block Graph

Joyentanuj Das, Sumit Mohanty

Let $D (G)$ be the distance matrix of a simple connected graph $G$ . The Hadamard product $D (G) \circ D (G)$ is called the squared distance matrix of $G$ , and is denoted by $Δ (G)$ . A…

cs.DS2025

Online Sparsification of Bipartite-Like Clusters in Graphs

Joyentanuj Das, Suranjan De, He Sun

Graph clustering is an important algorithmic technique for analysing massive graphs, and has been widely applied in many research fields of data science. While the objective of mos…

math.CO2023

On the maximum $A_{α}$ -spectral radius of unicyclic and bicyclic graphs with fixed girth or fixed number of pendant vertices

Joyentanuj Das, Iswar Mahato

For a connected graph $G$ , let $A (G)$ be the adjacency matrix of $G$ and $D (G)$ be the diagonal matrix of the degrees of the vertices in $G$ . The $A_{α}$ -matrix of $G$ is defined as…

math.CO2023

Inverse of the Squared Distance Matrix of a Complete Multipartite Graph

Joyentanuj Das, Sumit Mohanty

Let $G$ be a connected graph on $n$ vertices and $d_{ij}$ be the length of the shortest path between vertices $i$ and $j$ in $G$ . We set $d_{ii} = 0$ for every vertex $i$ in $G$ . The…

math.CO2023

On the spectral radius of clique trees with a given zero forcing number

Joyentanuj Das

Let $G (n, k)$ be the class of clique trees on $n$ vertices and zero forcing number $k$ , where $⌊ \frac{n}{2} ⌋ + 1 \leq k \leq n - 1$ and each block is a clique…

math.CO2023

Maximization of the spectral radius of block graphs with a given dissociation number

Joyentanuj Das, Sumit Mohanty

A connected graph is called a block graph if each of its blocks is a complete graph. Let $Bl (k, φ)$ be the class of block graphs on $k$ vertices with giv…

math.CO2022

On Sombor Index of Unicyclic graphs with a fixed number of pendant vertices

Joyentanuj Das, Yogesh Prajapaty

The Sombor index is a topological index in graph theory defined by Gutman in 2021. In this article we find the maximum Sombor index of unicyclic graphs with a fixed number of penda…

math.CO2022

On extremal Sombor index of trees with a given dissociation number $φ$

Joyentanuj Das

The Sombor index is a topological index in graph theory defined by Gutman in 2021. In this article, we find the maximum Sombor index of trees of order $n$ with a given dis…

math.CO2021

Proof of a Conjecture on Wiener Index and Eccentricity of a graph due to edge contraction

Joyentanuj Das, Ritabrata Jana

For a connected graph $G$ , the Wiener index, denoted by $W (G)$ , is the sum of the distance of all pairs of distinct vertices and the eccentricity, denoted by $ε (G)$ , is t…

math.CO2020

On Squared Distance Matrix of Complete Multipartite Graphs

Joyentanuj Das, Sumit Mohanty

Let $G = K_{n_{1}, n_{2}, \dots, n_{t}}$ be a complete $t$ -partite graph on $n = \sum_{i = 1}^{t} n_{i}$ vertices. The distance between vertices $i$ and $j$ in $G$ , denoted by $d_{ij}$ is defined…

math.CO2020

On the spectral radius of bi-block graphs with given independence number $α$

Joyentanuj Das, Sumit Mohanty

A connected graph is called a bi-block graph if each of its blocks is a complete bipartite graph. Let $B (k, α)$ be the class of bi-block graph on $k$ ve…

math.CO2020

Distance Matrix of Weighted Cactoid-type Digraphs

Joyentanuj Das, Sumit Mohanty

A strongly connected digraph is called a cactoid-type if each of its blocks is a digraph consisting of finitely many oriented cycles sharing a common directed path. In this article…

math.CO2019

Distance Matrix of a Multi-block Graph: Determinant and Inverse

Joyentanuj Das, Sumit Mohanty

A connected graph is called a multi-block graph if each of its blocks is a complete multi-partite graph. Building on the work of \cite{Bp3,Hou3}, we compute the determinant and inv…

math.CO2019

Distance Matrix of a Class of Completely Positive Graphs: Determinant and Inverse

Joyentanuj Das, Sachindranath Jayaraman, Sumit Mohanty

A real symmetric matrix $A$ is said to be completely positive if it can be written as $B B^{t}$ for some (not necessarily square) nonnegative matrix $B$ . A simple graph $G$ is called…

Counterexample to the Bougard-Joret Conjecture

A higher-connectivity spectral Ore theorem for triangle-free graphs

A sharp fixed-size spectral bound for kK3​-free graphs

Laplacian Bounds for the Dissociation Number of Regular Graphs of Matrix Rings

On the minimum spectral radius of unicyclic graphs with a given matching number

The exponential distance matrix of bi-block graphs

A q-analogue of distance matrix of bi-block graphs

On the Squared Distance Matrix of a Starlike Block Graph

Online Sparsification of Bipartite-Like Clusters in Graphs

On the maximum Aα​-spectral radius of unicyclic and bicyclic graphs with fixed girth or fixed number of pendant vertices

Inverse of the Squared Distance Matrix of a Complete Multipartite Graph

On the spectral radius of clique trees with a given zero forcing number

Maximization of the spectral radius of block graphs with a given dissociation number

On Sombor Index of Unicyclic graphs with a fixed number of pendant vertices

On extremal Sombor index of trees with a given dissociation number φ

Proof of a Conjecture on Wiener Index and Eccentricity of a graph due to edge contraction

On Squared Distance Matrix of Complete Multipartite Graphs

On the spectral radius of bi-block graphs with given independence number α

Distance Matrix of Weighted Cactoid-type Digraphs

Distance Matrix of a Multi-block Graph: Determinant and Inverse

Distance Matrix of a Class of Completely Positive Graphs: Determinant and Inverse

A sharp fixed-size spectral bound for $k K_{3}$ -free graphs

A $q$ -analogue of distance matrix of bi-block graphs

On the maximum $A_{α}$ -spectral radius of unicyclic and bicyclic graphs with fixed girth or fixed number of pendant vertices

On extremal Sombor index of trees with a given dissociation number $φ$

On the spectral radius of bi-block graphs with given independence number $α$