Per-spectral and adjacency spectral characterizations of a complete graph removing six edges
نویسندگان
چکیده
Cámara and Haemers (2014) investigatedwhen a complete graphwith some edges deleted is determined by its adjacency spectrum (DAS for short). They claimed: for anym ≥ 6 and every large enough n one can obtain graphswhich are not DAS by removingm edges from a complete graph Kn. LetGn denote the set of all graphs obtained from a complete graph Kn by deleting six edges. In this paper, we show that all graphs in Gn are uniquely determined by their permanental spectra. However, we show that for each n ≥ 7 or n = 5 there is just one pair of nonisomorphic cospectral graphs in Gn, and for n = 4 or 6 all graphs in Gn are DAS. © 2015 Elsevier B.V. All rights reserved.
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 203 شماره
صفحات -
تاریخ انتشار 2016