import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;


public class mortgage
{

	/**
	 * @param args
	 * @throws IOException 
	 */
	public static void main(String[] args) throws IOException
	{
		{
			BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
			String s;
			int m, x, y, n;
			double r, output;
			while(true)
			{
				s = br.readLine();
				m = s.indexOf(" ");
				x = Integer.valueOf(s.substring(0,m));
				s = s.substring(m+1);
				m = s.indexOf(" ");
				y = Integer.valueOf(s.substring(0,m));
				s = s.substring(m+1);
				m = s.indexOf(" ");
				n = Integer.valueOf(s.substring(0,m));
				r = Double.valueOf(s.substring(m+1));	
				
				if (x == 0 && y == 0 && n == 0 && r == 0) break;
				
				r = (1 + (r / 1200));
				
				output = (double) x;
				for (int i = 0; i < 12*n; i++)
				{
				 	output = r*output-y;
				}
				
				if (output <= 0) {
				System.out.println("YES");
				}
				else {
					System.out.println("NO");
				}
				
			}
		}

	}

}