A characterization of skew Hadamard matrices and doubly regular tournaments

2012/02/24 by Nozaki, Hiroshi, Suda, Sho
#05B20 #Combinatorics (math.CO) #FOS: Mathematics

paper · doi:10.48550/arxiv.1202.5374

Abstract

We give a new characterization of skew Hadamard matrices of size n in terms of the data of the spectra of tournaments of size n-2.

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