Question 59
Consider a subset $A$ of 84 elements of the set $\{1,2, \ldots, 169\}$ such that no two elements in the set add up to 169. Show that $A$ contains a perfect square.
MathNet 2008-part-01 — 165 problems (EN–VI) Question 59
Math Olympiad Vault · MathNet 2008-part-01 — 165 problems (EN–VI)