Spectral radius and Average 2-Degree sequence of a Graph
نویسندگان
چکیده
Let G be a simple connected graph of order n with average 2degree sequence M1 ≥ M2 ≥ · · · ≥ Mn. Let ρ(G) denote the spectral radius of the adjacency matrix of G. We show that for each 1 ≤ l ≤ n and for any b ≥ max {di/dj | i ∼ j}, ρ(G) ≤ Ml − b+ √ (Ml + b)2 + 4b ∑l−1 i=1(Mi −Ml) 2 with equality if and only if M1 = M2 = · · · = Mn.
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ورودعنوان ژورنال:
- Discrete Math., Alg. and Appl.
دوره 6 شماره
صفحات -
تاریخ انتشار 2014