Problem

Source: KJMO 2023 P7

Tags: number theory



Find the smallest positive integer $N$ such that there are no different sets $A, B$ that satisfy the following conditions. (Here, $N$ is not a power of $2$. That is, $N \neq 1, 2^1, 2^2, \dots$.) $A, B \subseteq \{1, 2^1, 2^2, 2^3, \dots, 2^{2023}\} \cup \{ N \}$ $|A| = |B| \geq 1$ Sum of elements in $A$ and sum of elements in $B$ are equal.