A note on finding large transversals efficiently

In an nxn array filled with symbols, a transversal is a collection of entries with distinct rows, columns and symbols. In this note we show that if no symbol appears more than ßn times, the array contains a transversal of size (1-ß/4 - o(1))n. In particular, if the array is filled with n symbols, ea...

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Bibliographic Details
Authors: Anastos, Michael, Morris, Patrick Wyndham|||0000-0001-9359-0748
Format: article
Publication Date:2025
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/431885
Online Access:https://hdl.handle.net/2117/431885
https://dx.doi.org/10.1002/jcd.21990
Access Level:Open access
Keyword:Àrees temàtiques de la UPC::Matemàtiques i estadística::Matemàtica discreta::Combinatòria
Description
Summary:In an nxn array filled with symbols, a transversal is a collection of entries with distinct rows, columns and symbols. In this note we show that if no symbol appears more than ßn times, the array contains a transversal of size (1-ß/4 - o(1))n. In particular, if the array is filled with n symbols, each appearing n times (an equi-n square), we get transversals of size (3/4 - o(1))n. Moreover, our proof gives a deterministic algorithm with polynomial running time, that finds these transversals.