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

string tb1 = "A123456789TJQK";
string tb2 = "DCHS";

bool cmp(string a,string b){
    a[0] = 'A'+tb2.find(a[0]);
    a[1] = 'A'+tb1.find(a[1]);
    b[0] = 'A'+tb2.find(b[0]);
    b[1] = 'A'+tb1.find(b[1]);	
    return a < b;
}

int Klim;

int sum[20210] = {};
int dp[110][20110];
int N,S,K;
vector<int> v;
int dfs(int x,int s){
    if( s < 0 ) return 0;
    if( dp[x][s] != -1 ) return dp[x][s];
    if( x == 0 ){
        return s == 0;
    }
    int ans = 0;
    for(int i = 0 ; ; i++){
        int c = i * x;
        if( c > s ) break;
        ans += dfs(x-1,s-c); 
		if( ans >= 1000000007 ) ans -= 1000000007;
    }
    return dp[x][s] = ans;
}



int main(){
    memset(dp,-1,sizeof(dp));
    cin >> N >> S >> K;
    S -= K*N*(N-1)/2;
    cout << dfs(N,S) << endl;
    
}