#include "bits/stdc++.h"
using namespace std;
const int MOD = 1000000007;

long long dp[101][200001];

int main(){
    int n,s,k;
    cin >> n >> s >> k;

    for(int i = 0; i <= s; i++){
        if(i%n == 0) dp[0][i] = 1;
    }
    for(int i = 1; i < n; i++){
        for(int j = 0; j <= s; j++){
            if(j-k*(n-i) < 0) dp[i][j] = 0;
            else dp[i][j] = (dp[i-1][j-k*(n-i)] + dp[i][j-(n-i)]) % MOD;
        }
    }
    cout << dp[n-1][s] << endl;
}