IMO Shortlist 2016 problem N2


Kvaliteta:
  Avg: 0,0
Težina:
  Avg: 6,0
Dodao/la: arhiva
3. listopada 2019.
LaTeX PDF

Let \tau(n) be the number of positive divisors of n. Let \tau_1(n) be the number of positive divisors of n which have remainders 1 when divided by 3. Find all positive integral values of the fraction \frac{\tau(10n)}{\tau_1(10n)}.

Izvor: https://www.imo-official.org/problems/IMO2016SL.pdf