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Asymptotic Improvements of Lower Bounds for the Least Common Multiples of Arithmetic Progressions

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 نشر من قبل Scott Kominers
 تاريخ النشر 2010
  مجال البحث
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For relatively prime positive integers $u_0$ and $r$, we consider the least common multiple $L_n:=mathrm{lcm}(u_0,u_1,ldots, u_n)$ of the finite arithmetic progression ${u_k:=u_0+kr}_{k=0}^n$. We derive new lower bounds on $L_n$ which improve upon those obtained previously when either $u_0$ or $n$ is large. When $r$ is prime, our best bound is sharp up to a factor of $n+1$ for $u_0$ properly chosen, and is also nearly sharp as $ntoinfty$.



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