MathDB
Remainders upon division by 30

Source: Finnish Mathematics Competition 2007, Final Round, Problem 1

November 14, 2011
ratioinequalitiesarithmetic sequencenumber theory unsolvednumber theory

Problem Statement

Show: when a prime number is divided by 30,30, the remainder is either 11 or a prime number. Is a similar claim true, when the divisor is 6060 or 9090?