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arXiv · 1701.08220

Transversals in generalized Latin squares

János Barát·Zoltán Lóránt Nagy
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Abstract

We are seeking a sufficient condition that forces a transversal in a generalized Latin square. A generalized Latin square of order $n$ is equivalent to a proper edge-coloring of $K_{n,n}$. A transversal corresponds to a multicolored perfect matching. Akbari and Alipour defined $l(n)$ as the least integer such that every properly edge-colored $K_{n,n}$, which contains at least $l(n)$ different colors, admits a multicolored perfect matching. They conjectured that $l(n)\leq n^2/2$ if $n$ is large enough. In this note we prove that $l(n)$ is bounded from above by $0.75n^2$ if $n>1$. We point out a connection to anti-Ramsey problems. We propose a conjecture related to a well-known result by Woolbright and Fu, that every proper edge-coloring of $K_{2n}$ admits a multicolored $1$-factor.

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János Barát, Zoltán Lóránt Nagy. 2017-01-27. Transversals in generalized Latin squares. https://arxiv.org/abs/1701.08220

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