Restricted completion of sparse partial Latin squares
Abstract
An partial Latin square is called -dense if each row and column has at most non-empty cells and each symbol occurs at most times in . An array where each cell contains a subset of is a -array if each symbol occurs at most times in each row and column and each cell contains a set of size at most . Combining the notions of completing partial Latin squares and avoiding arrays, we prove that there are constants such that, for every positive integer , if is an -dense partial Latin square, is an -array, and no cell of contains a symbol that appears in the corresponding cell of , then there is a completion of that avoids ; that is, there is a Latin square that agrees with on every non-empty cell of , and, for each satisfying , the symbol in position in does not appear in the corresponding cell of .
Cite
@article{arxiv.1608.07383,
title = {Restricted completion of sparse partial Latin squares},
author = {Lina J. Andrén and Carl Johan Casselgren and Klas Markström},
journal= {arXiv preprint arXiv:1608.07383},
year = {2019}
}
Comments
19 pages