Pairwise Sums
Source: Ukrainian Mathematical Olympiad 2024. Day 1, Problem 8.1, 9.1
March 19, 2024
number theoryDigits
Problem Statement
Oleksiy wrote several distinct positive integers on the board and calculated all their pairwise sums. It turned out that all digits from to appear among the last digits of these sums. What could be the smallest number of integers that Oleksiy wrote?Proposed by Oleksiy Masalitin