MathDB
M 25

Source:

May 25, 2007
Recursive Sequences

Problem Statement

Let {an}n1\{a_{n}\}_{n \ge 1} be a sequence of positive integers such that 0<an+1an2001    for all    nN.0 < a_{n+1}-a_{n}\le 2001 \;\; \text{for all}\;\; n \in \mathbb{N}. Show that there are infinitely many pairs (p,q)(p, q) of positive integers such that p>qp>q and aq    apa_{q}\; \vert \; a_{p}.