#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair <ll, ll> P;
#define rep(i,n) for ( int i =0 ; i < (n); i ++)
#define ALL(x) x.begin(),x.end()

template<class T>  bool chmax(T &a, T b) {if (a < b) {a = b;return true;}else return false;}
template<class T>  bool chmin(T &a, T b) {if (a > b) {a = b;return true;}else return false;}
const int INF = (1<<30)-1;
const ll LINF = 1e18;
const int mod = 1000000007;
#define LOCAL
#ifdef LOCAL
#define dbg(x) cerr << __LINE__ << " : " << #x << " = " << (x) << endl
#define vdbg(x) cerr << __LINE__ << " : " << #x << " = "; copy((x).begin(), (x).end(), ostream_iterator<ll>(cerr, "; ")); cerr << endl;
#define vvdbg(x) cerr << __LINE__ << " : " << #x << " = " << endl; for ( auto i: (x) ){ copy((i).begin(), (i).end(), ostream_iterator<ll>(cerr, "; ")); cerr << endl;}
#define pdbg(x) cerr << __LINE__ << " : " << #x << " = " ; for ( auto i: (x) ) cerr <<'(' << i.first<< ' ' << i.second << ')'<< ", "; cerr << endl;
#define vpdbg(x) cerr << __LINE__ << " : " << #x << " = " << endl ; for (auto j:(x) ) {for ( auto i: (j) ) cerr << '(' << i.first<< ' ' << i.second << ')'<< ", "; cerr << endl;}
#else 
#define dbg(x) true
#define vdbg(x) true
#define vvdbg(x) true
#define pdbg(x) true
#define vpdbg(x) true
#endif

int main() {
	//入力
	int n,s,k; scanf("%d %d %d",&n, &s, &k);
	int dp[101][20001];
	// dpを作っていく
	rep(i,20001) dp[0][i] = 0;
	rep(i, 101)dp[i][0] = 1;
	rep(i,n)rep(j,s){
		dp[i+1][j+1] =dp[i][j+1];
		if ( j-i >=0) dp[i+1][j+1] += dp[i+1][j-i] % mod;
		 dp[i+1][j+1] %= mod;
	}
	if (s - (n-1) * n /2 *k < 0) {
		cout << 0 << endl;
		return 0;
	}
	cout << dp[n][s - (n-1) * n /2 *k] << endl;


	// rep(i,10){
	// 	rep(j,10) cout << dp[i][j] << ' ';
	// 	cout << endl;
	// }

}