Samuel Orellana Mateo

arXiv2026

LU Factorization of Discrete Random Matrices

We consider the probability that a discrete random matrix $M_n(ξ)$ is \emph{strongly non-singular}, meaning all its leading principal submatrices are non-singular. This property is equivalent to the existence of an LU factorization. We show that for any discrete random variable $ξ$ with finite support and $|ξ|_\infty < 1$, there is a constant probability that $M_n(ξ)$ is strongly non-singular with a growth factor bounded by $n^{5/2+δ}$. Furthermore, we provide a tight asymptotic lower bound for this probability as $|ξ|_\infty \to 0$. Finally, we provide exact counts for strongly non-singular binary matrices up to $n=9$ and use these to derive improved upper bounds for the Bernoulli case.

math.NA↗

arXiv2026

Enumerating Prime Patterns in Juggling Variations

Juggling patterns can be mathematically modeled as closed walks within directed state graphs. In this paper, we present a unified framework of unbounded juggling patterns and its variations (including multiplex, colored, and passing) primarily through the formalism of the juggling state. By extending this state-based approach and utilizing combinatorial tools such as set partitions and filled Ferrers diagrams, we find and prove a new lower bound on the number of $b$-ball prime patterns with period $n$. Further, we determine exact counts for 2-ball multiplex, 1-ball passing, and 2-ball colored juggling patterns, as well as a lower bound for 2-ball passing. We also provide an extensive analysis of the asymptotic growth rates for these pattern counts. Finally, we formalize the infinite state graph, $G_\infty$, and utilize flip-reverse involutions to establish bijections between classes of prime patterns, exploring how fixing a specific state influences the enumeration of prime walks.

math.CO↗