Signed (0,2)‐graphs with few eigenvalues and a symmetric spectrum
نویسندگان
چکیده
We investigate properties of signed graphs that have few distinct eigenvalues together with a symmetric spectrum. Our main contribution is to determine all rectagraphs (triangle-free ( 0 , 2 ) $(0,2)$ -graphs) vertex degree at most 6 precisely two ± λ $\pm \lambda $ . Next, we consider what extent induced subgraphs graph are determined by their spectra. Lastly, classify spectrum three and give partial classification for -graphs four eigenvalues.
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ژورنال
عنوان ژورنال: Journal of Combinatorial Designs
سال: 2022
ISSN: ['1520-6610', '1063-8539']
DOI: https://doi.org/10.1002/jcd.21828