Renny P. Varghese and D. Susha

Notes on Number Theory and Discrete Mathematics

Print ISSN 1310–5132, Online ISSN 2367–8275

Volume 27, 2021, Number 1, Pages 208–220

DOI: 10.7546/nntdm.2021.27.1.208-220

**Full paper (PDF, 201 Kb)**

## Details

### Authors and affiliations

Renny P. Varghese

*Department of Mathematics, Catholicate College
Pathanamthitta, Kerala 689 645, India*

D. Susha

*Department of Mathematics, Catholicate College
Pathanamthitta, Kerala 689 645, India*

### Abstract

In this paper we introduce a new corona-type product of graphs namely *duplication corresponding corona*. Here we mainly determine the adjacency, Laplacian and signless Laplacian spectra of the new graph product. In addition to that, we find out the incidence energy, the number of spanning trees, Kirchhoff index and Laplacian-energy-like invariant of the new graph. Also we discuss some new classes of cospectral graphs.

### Keywords

- Spectrum
- Corona
- Duplication graph
- Incidence energy
- Spanning tree
- Kirchhoffindex
- Laplacian-energy-like invariant

### 2010 Mathematics Subject Classification

- 05C50
- 05C76

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## Cite this paper

Varghese, R. P. & Susha, D. (2021). On the spectra of a new duplication based corona of graphs. *Notes on Number Theory and Discrete Mathematics*, 27(1), 208-220, DOI: 10. 7546/nntdm.2021.27.1.208-220.