# Problem C. 1304. (September 2015)

**C. 1304.** Two players are playing the following game: They take turns in writing a natural number 1 to 10 on a blackboard. It is only allowed to write a number that does not divide any of the numbers written on the board previously. If a player is not able to write a new number on the board, he loses the game. Show that the starting player has a winning strategy.

(5 pont)

**Deadline expired on October 12, 2015.**

### Statistics:

221 students sent a solution. 5 points: 80 students. 4 points: 19 students. 3 points: 10 students. 2 points: 9 students. 1 point: 56 students. 0 point: 45 students. Unfair, not evaluated: 2 solutionss.

Problems in Mathematics of KöMaL, September 2015