Construction of Simultaneous Cospectral Graphs for Adjacency, Laplacian and Normalized Laplacian Matrices
Kragujevac Journal of Mathematics, Tome 47 (2023) no. 6, p. 947
In this paper we construct several classes of non-regular graphs which are co-spectral with respect to all the three matrices, namely, adjacency, Laplacian and normalized Laplacian, and hence we answer a question asked by Butler \cite{But1}. We make these constructions starting with two pairs ($G_{1}$, $H_{1}$) and ($G_{2}$, $H_{2}$) of $A$-cospectral regular graphs, then considering the subdivision graphs $S(G_{i})$ and R-graphs $\mathcal{R}(H_{i})$, $i=1,2$, and finally making some kind of partial joins between $S(G_{1})$ and $\mathcal{R}(G_{2})$ and $S(H_{1})$ and $\mathcal{R}(H_{2})$. Moreover, we determine the number of spanning trees and the Kirchhoff index of the newly constructed graphs.
Classification :
05C50
Keywords: Adjacency matrix, Laplacian matrix, normalized Laplacian matrix, cospectral graphs
Keywords: Adjacency matrix, Laplacian matrix, normalized Laplacian matrix, cospectral graphs
@article{KJM_2023_47_6_a8,
author = {Arpita Das and Pratima Panigrahi},
title = {Construction of {Simultaneous} {Cospectral} {Graphs} for {Adjacency,} {Laplacian} and {Normalized} {Laplacian} {Matrices}},
journal = {Kragujevac Journal of Mathematics},
pages = {947 },
year = {2023},
volume = {47},
number = {6},
language = {en},
url = {http://geodesic.mathdoc.fr/item/KJM_2023_47_6_a8/}
}
TY - JOUR AU - Arpita Das AU - Pratima Panigrahi TI - Construction of Simultaneous Cospectral Graphs for Adjacency, Laplacian and Normalized Laplacian Matrices JO - Kragujevac Journal of Mathematics PY - 2023 SP - 947 VL - 47 IS - 6 UR - http://geodesic.mathdoc.fr/item/KJM_2023_47_6_a8/ LA - en ID - KJM_2023_47_6_a8 ER -
%0 Journal Article %A Arpita Das %A Pratima Panigrahi %T Construction of Simultaneous Cospectral Graphs for Adjacency, Laplacian and Normalized Laplacian Matrices %J Kragujevac Journal of Mathematics %D 2023 %P 947 %V 47 %N 6 %U http://geodesic.mathdoc.fr/item/KJM_2023_47_6_a8/ %G en %F KJM_2023_47_6_a8
Arpita Das; Pratima Panigrahi. Construction of Simultaneous Cospectral Graphs for Adjacency, Laplacian and Normalized Laplacian Matrices. Kragujevac Journal of Mathematics, Tome 47 (2023) no. 6, p. 947 . http://geodesic.mathdoc.fr/item/KJM_2023_47_6_a8/