Easy combinatorics about finding minimum integer
Source: BdMO 2022 Secondary P4
April 12, 2022
combinatorics
Problem Statement
Pratyya and Payel have a number each, and respectively, where Everyday, Pratyya multiplies his number by and then subtracts from it, and Payel multiplies his number by and then add to it. In other words, on the first day their numbers will be and respectively. Find minimum integer with proof such that if then Pratyya's number will be larger than Payel's number everyday.