2024/07/06 by Toghrul Karimov, Karimov, Toghrul, Florian Luca +7 · 1 citation
Computer Science · #Advanced Algebra and Logic #Computability, Logic, AI Algorithms #FOS: Computer and information sciences #Logic in Computer Science (cs.LO)
paper · pdf · doi:10.48550/arxiv.2407.05191
openalex publication_date 2024/07/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We prove that for any integers α, β> 1, the existential fragment of the first-order theory of the structure ⟨ ℤ; 0,1,<, +, αℕ, βℕ⟩ is decidable (where αℕ is the set of positive integer powers of α, and likewise for βℕ). On the other hand, we show by way of hardness that decidability of the existential fragment of the theory of ⟨ ℕ; 0,1, <, +, x↦ αx, x ↦ βx⟩ for any multiplicatively independent α,β> 1 would lead to mathematical breakthroughs regarding base-α and base-β expansions of certain transcendental numbers.