Non-regular square bipartite designs
type: Item
instance of: scholarly article
title: Non-regular square bipartite designs
zbMATH Open document ID: 0998.15021
DOI: 10.1016/S0024-3795(01)00570-5
author: Caterina De Simone
author: Grigor Gasparyan
author: Paolo Nobili
published in: Linear Algebra and its Applications
publication date: 2002-06-27T00:00:00Z
review text: This paper gives a classification of a new type of non-regular bipartite design generalizing most of the existing results. The case dealt with is a nonregular \((d,\lambda)\) square bipartite design \((A,B)\), \(A^TB=\lambda +\text{diag}(d)\), \(d\) having full support and \(\forall i\neq j\), \(a_{i.} \cdot b_{j.}\geq\lambda\). Then \((A,B)\) is a degenerate projective plane design or is one of 5 special types. It is also proved that this generalizes various previous classifications.
Mathematics Subject Classification ID: 15B36
Mathematics Subject Classification ID: 05B20
Mathematics Subject Classification ID: 15A24
Mathematics Subject Classification ID: 05B30
zbMATH DE Number: 1760973
zbMATH Keywords: 0-1 matrices
zbMATH Keywords: design theory
zbMATH Keywords: non-regular bipartite design
zbMATH Keywords: degenerate projective plane
reviewed by: Ki Hang Kim
MaRDI profile type: Publication
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description: scientific article; zbMATH DE number 1760973