The roots of the independence polynomial of a clawfree graph
نویسندگان
چکیده
The independence polynomial of a graph G is the polynomial ΣA x |A|, summed over all independent subsets A ⊆ V (G). We prove that if G is clawfree, then all the roots of its independence polynomial are real. This extends a theorem of Heilmann and Lieb [12], answering a question posed by Hamidoune [11] and Stanley [15].
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 97 شماره
صفحات -
تاریخ انتشار 2007