#include <bits/stdc++.h>

#define mp       make_pair
#define mt	 make_tuple
#define pb       push_back
#define rep(i,n) for(int i=0;i<(n);i++)

using namespace std;

typedef    long long          ll;
typedef    unsigned long long ull;
typedef    pair<int,int>      pii;
typedef    pair<long,long>    pll;

const int INF=1<<29;
const double EPS=1e-9;
const int MOD = 1000000007;

const int dx[]={1,0,-1,0},dy[]={0,-1,0,1};
int N,S,K;
int dp[110][20010];

int main(){
  cin >> N >> S >> K;
  for (int i = 0; i <= S; i+=N){
    dp[1][i] = 1;
  }

  for (int i = 2; i <= N; i++){
    int mult = N + 1 - i;
    for (int j = 0; j <= S; j++){
      if (j >= K * mult){
	dp[i][j] += dp[i - 1][j - K * mult];
	dp[i][j] %= MOD;
      }
    }
    for (int j = 0; j <= S; j++){
      if (j - mult >= 0){
	dp[i][j] += dp[i][j - mult];
	dp[i][j] %= MOD;
      }
    }
  }
  cout << dp[N][S] << endl;
  return 0;
}