MathDB

Moldova JTST 2019 P1

Source: Moldova JTST 2019

April 19, 2019

number theory

Problem Statement

Let

n

be a positive integer. From the set

A=\{1,2,3,...,n\}

an element is eliminated. What's the smallest possible cardinal of

A

and the eliminated element, since the arithmetic mean of left elements in

A

\frac{439}{13}