MathDB
Infinite sequence of positive integers (2015 OMCS #5)

Source:

May 16, 2015
number theoryDivisibilitySequence

Problem Statement

Determine if there exists an infinite sequence of not necessarily distinct positive integers a1,a2,a3,a_1, a_2, a_3,\ldots such that for any positive integers mm and nn where 1m<n1 \leq m < n, the number am+1+am+2++ana_{m+1} + a_{m+2} + \ldots + a_{n} is not divisible by a1+a2++ama_1 + a_2 + \ldots + a_m.