Középiskolai Matematikai és Fizikai Lapok
Informatika rovattal
Kiadja a MATFUND Alapítvány
Már regisztráltál?
Új vendég vagy?

Cikkeink (Mathematics)

MathematicsKürschák contest

Problems of Kürschák competition 2025

Editor

1. Fix a positive integer \(\displaystyle n\) and write the numbers \(\displaystyle 0, 1, \ldots, n-1\) on a whiteboard in some order. Two numbers form an inversion if the greater precedes the smaller. A number \(\displaystyle k\) is called special if \(\displaystyle k\) forms inversions with exactly \(\displaystyle k\) other numbers. At most how many special numbers can we have on the board?