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Log-concavity of Whitney numbers of Dowling lattices. (English) Zbl 0918.05003
This paper shows that the generating polynomial of Whitney numbers of the Dowling lattices has only real roots. This gives a new proof (through a result of Newton) that these Whitney numbers form strictly log-concave sequences.

##### MSC:
 05A15 Exact enumeration problems, generating functions 06C10 Semimodular lattices, geometric lattices
Full Text:
##### References:
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