MathDB

Regional Olympiad - FBH 2009 Grade 11 Problem 3

Source: Regional Olympiad - Federation of Bosnia and Herzegovina 2009

September 28, 2018

boardMinimalcombinatorics

Problem Statement

There are

n

positive integers on the board. We can add only positive integers

c=\frac{a+b}{a-b}

, where

a

and

b

are numbers already writted on the board.

a)

Find minimal value of

n

, such that with adding numbers with described method, we can get any positive integer number written on the board

b)

For such

n

, find numbers written on the board at the beginning