Back to Problems
erdos_263.variants.doubly_exponential_all_but_countable
Specification
Koizumi [Ko25] showed that $a_n = \lfloor \alpha^{2^n} \rfloor$ is an irrationality sequence for all but countably many $\alpha > 1$. [Ko25] Koizumi, J., Irrationality of the reciprocal sum of doubly exponential sequences, arXiv:2504.05933 (2025).
Lean 4 Statement
theorem erdos_263.variants.doubly_exponential_all_but_countable :
∀ᶠ (α : ℝ) in .cocountable, α > 1 → IsIrrationalitySequence (fun n : ℕ => ⌊α ^ 2 ^ n⌋₊)
Browse
All Problems
Explore all 300 unsolved conjectures.
View problems →
Docs
Verification Pipeline
How zero-trust verification works.
Read docs →
Evaluation Results
Recent Submissions
No submissions yet. Be the first to attempt this problem.