无尽的平方自由数位走行
Dead ends in square-free digit walks
AI总结:
该研究证明了在平方自由数位走行中,死胡同的渐近密度远低于预测值,且通过形式化方法给出了闭合表达式。
摘要:
我们研究了平方自由数位走行中的'死胡同':即平方自由整数N,使得在基数b下,每一个一位扩展bN+d都不是平方自由的。在十进制中,Miller等人提出的随机独立模型表明,无限平方自由走行出现的概率接近1,对应着渐近死胡同密度约为5.218×10^-5。我们证明了真正的渐近死胡同密度满足[c_dead ≈ 1.317×10^-9],大约比预测值小一个数量级为4×10^4。对于每个基数b≥2,我们证明死胡同密度存在且由一个闭合表达式(作为有限交替欧拉乘积之和)给出。该论证在Lean/Mathlib中完全形式化,并由AxiomProver从问题的自然语言陈述自动生成。
英文摘要:
We study "dead ends" in square-free digit walks: square-free integers $N$ such that, in base $b$, every one-digit extension $bN+d$ is non-square-free. In base $10$, the stochastic independence model of Miller et al. suggests that infinite square-free walks occur with probability near $1$, corresponding to an asymptotic dead-end density of $\approx 5.218\times 10^{-5}$. We prove that the true asymptotic dead-end density satisfies \[ c_{\mathrm{dead}} \approx 1.317\times 10^{-9}, \] roughly a factor of $\sim 4\times 10^4$ smaller than the prediction. For every base $b\geq 2$, we prove that dead-end densities exist and are given by a closed-form expression (as a finite alternating sum of Euler products). The argument is fully formalized in Lean/Mathlib, and was produced automatically by AxiomProver from a natural-language statement of the problem.
机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。