Proof of a conjecture of Graham and Lovász concerning unimodality of coefficients of the distance characteristic polynomial of a tree
نویسندگان
چکیده
We establish a conjecture of Graham and Lovász that the (normalized) coefficients of the distance characteristic polynomial of a tree are unimodal; we also prove they are log-concave. Email addresses: [email protected] (Ghodratollah Aalipour), [email protected] (Aida Abiad), [email protected] (Zhanar Berikkyzy), [email protected] (Leslie Hogben), [email protected] (Franklin H. J. Kenter), [email protected] (Jephian C.-H. Lin), [email protected] (Michael Tait) Preprint submitted to Elsevier July 10, 2015
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