Strong cospectrality in trees
Algebraic Combinatorics, Volume 6 (2023) no. 4, pp. 955-963.

We prove that no tree contains a set of three vertices which are pairwise strongly cospectral. This answers a question raised by Godsil and Smith in 2017.

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DOI: 10.5802/alco.288
Classification: 05C50, 05C31, 05C05
Keywords: strongly cospectral vertices, trees, continued fractions

Coutinho, Gabriel 1; Juliano, Emanuel 1; Spier, Thomás Jung 1

1 Universidade Federal de Minas Gerais Dept. of Computer Science Rua Reitor Píres Albuquerque, ICEx - Pampulha Belo Horizonte - MG 31270-901 (Brazil)
License: CC-BY 4.0
Copyrights: The authors retain unrestricted copyrights and publishing rights
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Coutinho, Gabriel; Juliano, Emanuel; Spier, Thomás Jung. Strong cospectrality in trees. Algebraic Combinatorics, Volume 6 (2023) no. 4, pp. 955-963. doi : 10.5802/alco.288. https://alco.centre-mersenne.org/articles/10.5802/alco.288/

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