On eigenvalue multiplicity in signed graphs
نویسندگان
چکیده
منابع مشابه
Eigenvalue Multiplicity in Cubic Graphs
Let G be a connected cubic graph of order n with μ as an eigenvalue of multiplicity k. We show that (i) if μ 6∈ {−1, 0} then k ≤ 12n, with equality if and only if μ = 1 and G is the Petersen graph; (ii) If μ = −1 then k ≤ 12n + 1, with equality if and only if G = K4; (iii) If μ = 0 then k ≤ 12n+ 1, with equality if and only if G = 2K3. AMS Classification: 05C50
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2020
ISSN: 0012-365X
DOI: 10.1016/j.disc.2020.111982