Original scientific paper

Under a mild condition, Ryser's Conjecture holds for every \( n:= 4h^2\) with h>1 odd and non square-free

Luis H. Gallardo ; Univ Brest, UMR CNRS 6 205, Laboratoire de Math´ematiques de Bretagne Atlantique, Brest, France

Abstract

We prove, under a mild condition, that there is no circulant Hadamard matrix \( H\) with \(n >4\) rows when
\(\sqrt{n/4}\) is not square-free. The proof introduces a new method to attack
Ryser's Conjecture, that is a long standing difficult conjecture.

Keywords

Circulant matrices; Hadamard matrices; Sums of roots of unity; Complex unit circle; Cyclotomic fields

Hrčak ID:

252594

URI

https://hrcak.srce.hr/252594

Publication date:

10.3.2021.

Visits: 494 *