#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 memo(int pos, int sum){
  if (sum > S){
    return 0;
  }
  if (pos == N - 1){
    return 1;
  }
  if (dp[pos][sum] >= 0){
    return dp[pos][sum];
  }
  int res = 0;
  for (int i = 0; i*(N - pos) <= S; i++){
    res += memo(pos + 1, sum + i * (N - pos));
    res %= MOD;
  }
  return dp[pos][sum] = res;
}
int main(){
  cin >> N >> S >> K;
  memset(dp, -1, sizeof(dp));
  S -= N * (N - 1) / 2 * K;
  cout << memo(0, 0) << endl;
  return 0;
}