#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

int main() {
  int a, b, c;
  cin >> a >> b >> c;
  int n = ceil((double)a / b);
  int m = ceil((double)a / c);
  if ((double)m / n <= 2. / 3) puts("YES");
  else puts("NO");
  return 0;
}