MathDB
Ez pz combinatorics

Source: Moldova TST 2019

March 8, 2019
combinatoricsTSTeasy

Problem Statement

On the table there are written numbers 673,674,,2018,2019.673, 674, \cdots, 2018, 2019. Nibab chooses arbitrarily three numbers a,ba,b and cc, erases them and writes the number min(a,b,c)3\frac{\min(a,b,c)}{3}, then he continues in an analogous way. After Nibab performed this operation 673673 times, on the table remained a single number kk. Prove that k(0,1).k\in(0,1).