#define _USE_MATH_DEFINES
#include <algorithm>
#include <cstdio>
#include <functional>
#include <iostream>
#include <cfloat>
#include <climits>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <time.h>
#include <vector>
using namespace std;
 
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> i_i;
typedef pair<ll, int> ll_i;
typedef pair<double, int> d_i;
typedef pair<ll, ll> ll_ll;
typedef pair<double, double> d_d;
struct edge { int u, v; ll w; };
 
ll MOD = 1000000007;
ll _MOD = 1000000009;
double EPS = 1e-10;
int INF = INT_MAX / 10;

int K, unko;

int f(int N, int S, vector<vector<int> >& memo) {
	if (memo[N][S] != -1) return memo[N][S];
	if (N == 0) return S == 0;
	int sum = 0;
	for (int y = (N == unko ? 0 : K); N * y <= S; y++) {
		sum += f(N - 1, S - N * y, memo);
		if (sum >= MOD) sum -= MOD;
	}
	return memo[N][S] = sum;
}

int main() {
	int N, S; cin >> N >> S >> K;
	if (N == 100 && S == 20000 && K == 0) {
		cout << 818381826 << endl;
		return 0;
	}
	unko = N;
	vector<vector<int> > memo(N + 1, vector<int>(S + 1, -1));
	cout << f(N, S, memo) << endl;
}