MathDB

2

Part of 2012 Canadian Mathematical Olympiad Qualification Repechage

Problems(1)

d(n)+d(n+1)=5

Source: Canadian Repêchage 2012: Problem 2

5/19/2014
Given a positive integer mm, let d(m)d(m) be the number of positive divisors of mm. Determine all positive integers nn such that d(n)+d(n+1)=5d(n) +d(n+ 1) = 5.
modular arithmeticnumber theory proposednumber theory