大阶Davenport-Schinzel序列中鸽巢界渐近紧性
Asymptotic Tightness of the Pigeonhole Bound for Large-Order Davenport-Schinzel Sequences
AI总结:
该研究证明了在特定条件下,大阶Davenport-Schinzel序列的鸽巢界是渐近紧的,并确定了其主导常数和一般形式。
摘要:
我们证明当s/√m→∞时,鸽巢上界λ(s,m)≤C(m,2)(s+1)是渐近紧的。特别地,在此情况下,λ(s,m)~C(m,2)s。作为推论:λ(n,n)/n³→1/2,解决了之前已知的区间[1/3,1/2]中的主导常数;更一般地,对于任何常数a,b>0,λ(an,bn)~(ab²/2)n³。
英文摘要:
We prove that the pigeonhole upper bound $λ(s,m) \leq \binom{m}{2}(s+1)$ is asymptotically tight whenever $s/\!\sqrt{m} \to \infty$. In particular, $λ(s,m) \sim \binom{m}{2}\,s$ in this regime. As corollaries: $λ(n,n)/n^3 \to \frac{1}{2}$, resolving the leading constant from the previously known interval $[\frac{1}{3}, \frac{1}{2}]$; and more generally $λ(an,bn) \sim \frac{ab^2}{2}\,n^3$ for any constants $a,b > 0$.
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。