Subsquares in random Latin squares and rectangles

Autor: Divoux, Alexander, Kelly, Tom, Kennedy, Camille, Sidhu, Jasdeep
Rok vydání: 2023
Předmět:
Druh dokumentu: Working Paper
Popis: A $k \times n$ partial Latin rectangle is \textit{$C$-sparse} if the number of nonempty entries in each row and column is at most $C$ and each symbol is used at most $C$ times. We prove that the probability a uniformly random $k \times n$ Latin rectangle, where $k < (1/2 - \alpha)n$, contains a $\beta n$-sparse partial Latin rectangle with $\ell$ nonempty entries is $(\frac{1 \pm \varepsilon}{n})^\ell$ for sufficiently large $n$ and sufficiently small $\beta$. Using this result, we prove that a uniformly random order-$n$ Latin square asymptotically almost surely has no Latin subsquare of order greater than $c\sqrt{n\log n}$ for an absolute constant $c$.
Comment: 11 pages; 1 page appendix, corrected a typo in random Steiner system conjecture
Databáze: arXiv