ab222 ... 231 is divisible by 73, cd222... 231 is divisible by 79
Source: Mediterranean Mathematical Olympiad 2022 P2 MMC
September 21, 2022
number theorydivisibleDigits
Problem Statement
(a) Decide whether there exist two decimal digits and , such that every integer with decimal representation is divisible by .
(b) Decide whether there exist two decimal digits and , such that every integer with decimal representation is divisible by .