Nicholas J. Cavenagh
A uniqueness result for $3$-homogeneous latin trades

Comment.Math.Univ.Carolin. 47,2 (2006) 337-358.

Abstract:A latin trade is a subset of a latin square which may be replaced with a disjoint mate to obtain a new latin square. A $k$-homogeneous latin trade is one which intersects each row, each column and each entry of the latin square either $0$ or $k$ times. In this paper, we show that a construction given by Cavenagh, Donovan and Dr\'apal for $3$-homogeneous latin trades in fact classifies every minimal $3$-homogeneous latin trade. We in turn classify all $3$-homogeneous latin trades. A corollary is that any $3$-homogeneous latin trade may be partitioned into three, disjoint, partial transversals.

Keywords: latin square, latin trade, critical set
AMS Subject Classification: 05B15

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