#include <iostream>

void solve() {
    int a, b, c;
    std::cin >> a >> b >> c;

    int d = (a + b - 1) / b;
    std::cout << (a <= d * 2 / 3 * c ? "YES" : "NO") << std::endl;
}

int main() {
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    solve();

    return 0;
}