MathDB
Good set for all positive integers

Source: Bulgarian MO 2007, Day 2, Problem 4

May 16, 2007
combinatorics proposedcombinatorics

Problem Statement

Let k>1k>1 be a given positive integer. A set SS of positive integers is called good if we can colour the set of positive integers in kk colours such that each integer of SS cannot be represented as sum of two positive integers of the same colour. Find the greatest tt such that the set S={a+1,a+2,,a+t}S=\{a+1,a+2,\ldots ,a+t\} is good for all positive integers aa.
A. Ivanov, E. Kolev