#include <iostream>
#include <algorithm>
#include <functional>
#include <string>
#include <climits>
#include <vector>
#include <numeric>
#include <complex>
#include <map>
#include <bitset>
#include <stack>
#include <queue>
using namespace std;

#define __int64 long long
#define long __int64
#define REP(i,a,b) for(int i=a;i<b;i++)
#define rep(i,n) REP(i,0,n)
const int Vecy[4] = {0,-1,0,1};
const int Vecx[4] = {1,0,-1,0};

const int modd = 1000000000 + 7;

long comb2_data[20001][101] = {0};
long comb2(int cnt, int n){
//	cout << "--" << cnt << "<" << n << "--" << endl;
	
	long result;
	long cnti;
	
	if(n == 2){
	//	cout << "COMB2(" << cnt << "," << n << ") = " << (cnt + 2) / 2 << endl;
		return ((cnt + 2) / 2) % modd;
	}
	if(n == 1){
	//	cout << "COMB2(" << cnt << "," << n << ") = " << 1 << endl;
	//	cout << "!?" << endl;
		return cnt + 1;
	
	}else if(cnt == 0){
	//	cout << "COMB2(" << cnt << "," << n << ") = " << 1 << endl;
	//	cout << "cnt0" << endl;
		return 1;
	}else{
		if(comb2_data[cnt][n] != 0){
			//cout << "COMB2(" << cnt << "," << n << ") = " << comb2_data[cnt][n] << endl;
			return comb2_data[cnt][n];
		}
		
		result = 0;
		cnti = cnt;
		while(cnti >= 0){
			result += comb2(cnti, n-1);
			result %= modd;
			cnti -= n;
		}
		
	//	cout << "COMB2(" << cnt << "," << n << ") = " << result << endl;
		comb2_data[cnt][n] = result;
		return result;
	}
}


int main(){
	int n,s,k;
	int ans = 0;
	int mind;
	int test;
	int cnt;
	cin >> n >> s >> k;
	if(k == 0){
		mind = 0;
	}else{
		mind = (n - 1) * n / 2 * k;
	}
	
	cnt = s - mind;
//	cout << mind << endl;
//	cout << cnt << endl;
	
	if(cnt < 0){
		cout << 0 << endl;
		return 0;
	}else{
		ans = 1;
		
		cout << comb2(cnt, n) << endl;
	}
    
    return 0;
}