import java.util.*;

public class Yukicoder218{
	public static void main(String[] args){
		Scanner scan = new Scanner(System.in);
		int a = scan.nextInt();
		int b = scan.nextInt();
		int c = scan.nextInt();
		double bsozai = a / (b + 0.0);
		double csozai = a / (c + 0.0);
		if(Math.ceil(csozai) > bsozai * 2 / 3)	System.out.println("NO");
		else									System.out.println("YES");
	}
}