Skip to content / Đến nội dung
ThichHocToan.com

MathNet 2022-part-04 — 197 problems (EN–VI) Question 142

Math Olympiad Vault · MathNet 2022-part-04 — 197 problems (EN–VI)

Question 142

Let $S(n)$ be the sum of divisors of $n$ (for example $S(6) = 1+2+3+6 = 12$). Find all $n$ for which $S(2n) = 3S(n)$.