A simple proof of an inequality connecting the alternating number of independent sets and the decycling number
نویسندگان
چکیده
If sk denotes the number of independent sets of cardinality k and α(G) is the size of a maximum independent set in graph G, then I(G;x) = s0 + s1x+ ...+ sα(G)x α(G) is the independence polynomial of G [8]. In this paper we provide an elementary proof of the inequality |I(G;−1)| ≤ 2, where φ(G) is the decycling number of G.
منابع مشابه
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عنوان ژورنال:
- Discrete Mathematics
دوره 311 شماره
صفحات -
تاریخ انتشار 2011