Problem

Source: ToT - 2001 Fall Senior A-Level #2

Tags: number theory, least common multiple, induction, number theory unsolved



Do there exist positive integers $a_1<a_2<\ldots<a_{100}$ such that for $2\le k\le100$, the least common multiple of $a_{k-1}$ and $a_k$ is greater than the least common multiple of $a_k$ and $a_{k+1}$?