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

#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
#define pb push_back
#define mp make_pair

int c;

int memo[510][510];
bool dp(int w, int k) {
	if (w < 0) return false;
	if (w == k) return true;
	if (memo[w][k] != -1) return memo[w][k];

	for (int i = 1; i <= k-c; i++) {
		if (dp(w-(k-1), i)) return memo[w][k] = true;
	}

	return memo[w][k] = false;
}

int main() {
	cin.tie(0)->sync_with_stdio(0);
	cin.exceptions(cin.failbit);

	memset(memo, -1, sizeof memo);

	int w, k;
	cin >> w >> k >> c;

	if (dp(w, k)) cout << "yes" << endl;
	else cout << "no" << endl;
}