Recursive Prime Factorizations: Dyck Words as Numbers
Ralph L. Childress
TL;DR
This work introduces Recursive Prime Factorizations (RPF), a framework mapping numbers to Dyck words via recursive prime-factor encodings in a nonpositional numeral system. It develops the Standard Minimal RPF Natural Interpretation $\text{RPF}_{\mathbb{N}_{r_{\text{min}}}}$ with the Dyck-language-based domain $\mathcal{D}_{r_{\text{min}}}$, and proves a precise bijection with $\mathbb{N}$ through the spelling $\upgamma_{\mathbb{N}_r}$ and evaluation $\upalpha_{\mathbb{N}_{r_{\text{min}}}}$; it also shows $\mathcal{D}_{r_{\text{min}}}$ is a proper subset of the Dyck language $\mathcal{D}$. The paper then extends to a Standard Minimal RPF Superrational Interpretation, introducing the superrational numbers $\mathbb{S}$ and a corresponding two-symbol spelling/evaluation system that yields a surjective map from a Dyck-based language $\mathcal{D}_{r_{\text{qmin}}}$ to $\mathbb{S}$, and develops the mutual inverses $\upgamma_{\mathbb{S}_r}$ and $\upalpha_{\mathbb{S}_{r\text{min}}}$. Further, it surveys Dyck-complete interpretations where the entire Dyck language underlies the numeral system, and outlines rich directions for future work, including stripe analysis, learnability with lossless factorization trees, grammar-based pattern detection, and automata-theoretic characterizations of recursive prime factorizations. The results illuminate a grammar-centric perspective on number representations with potential crossovers to formal languages, cryptography, and computational learnability.
Abstract
I propose a class of non-positional numeral systems where numbers are represented by Dyck words, with the systems arising from a recursive extension of prime factorization. After describing two proper subsets of the Dyck language capable of uniquely representing all natural numbers and a superset of the rational numbers respectively, I consider "Dyck-complete" languages, in which every member of the Dyck language represents a number. I conclude by suggesting possible research directions.
