#include <iostream>
#include <ctime>
using namespace std;
const int mod = 1000000007;
template <int mod>
struct ModInt{
  int n;
  ModInt():n(0){}
  ModInt(int n_):n(n_ >= 0 ? n_%mod : mod - ((-n_)%mod) ){}

  ModInt &operator+=(const ModInt &p){
    if((n+=p.n) >= mod)n-=mod;
    return *this;
  }
  ModInt &operator-=(const ModInt &p){
    n+=mod-p.n;
    if(n >= mod)n-=mod;
    return *this;
  }
  ModInt &operator*=(const ModInt &p){
    n = (int) ((1LL*n*p.n)%mod);
    return *this;
  }
  ModInt &operator/=(const ModInt &p){
    *this *= p.inverse();
    return *this;
  }
  ModInt operator-() const {return ModInt(-n);}
  ModInt operator+(const ModInt &p) const {return ModInt(*this) += p;}
  ModInt operator-(const ModInt &p) const {return ModInt(*this) -= p;}
  ModInt operator*(const ModInt &p) const {return ModInt(*this) *= p;}
  ModInt operator/(const ModInt &p) const {return ModInt(*this) /= p;}

  bool operator==(const ModInt &p) const {return n==p.n;}
  bool operator!=(const ModInt &p) const {return n!=p.n;}

  ModInt inverse() const {
    int a = n,b = mod,u = 1,v = 0;
    while(b){
      int t = a/b;
      a -= t*b; swap(a,b);
      u -= t*v; swap(u,v);
    }
    return ModInt(u);
  }

  ModInt pow(int64_t z) const {
    ModInt ret(1),mul(n);
    while(z > 0){
      if(z & 1) ret *= mul;
      mul *= mul;
      z >>= 1;
    }
    return ret;
  }

  friend ostream &operator<<(ostream &os, const ModInt &p){
    return os << p.n;
  }
  friend istream &operator>>(istream &is, ModInt &a){
    int64_t t;
    is >> t;
    a = ModInt<mod> (t);
    return (is);

  }
};
using mint = ModInt<mod>;
mint dp[101][20001];
int main(){
	//int ti = clock();
	int n,s,k;cin>>n>>s>>k;
	if(((n+(n-1))/2)*((n+(n-1))/2+1)/2*k > s){
		cout << 0 << endl;
		return 0;
	}
	s -= ((n+(n-1))/2)*((n+(n-1))/2+1)/2*k;
	dp[0][0] = 1;
	for(int i = 0; n > i; i++){
		for(int j = 0; s >= j; j++){
			if(dp[i][j] != 0){
				for(int l = 0; s >= j+l*(n-i); l++){
					dp[i+1][j+l*(n-i)]+=dp[i][j];
				}
			}
		}
		//cout << i << endl;
	}
	// for(int i = 0; n >= i; i++){
	// 	for(int j = 0; s >= j; j++){
	// 		cout << dp[i][j] << " ";

	// 	}
	// 	cout << endl;
	// }
	cout << dp[n][s] << endl;

	//cout << (double)ti/CLOCKS_PER_SEC << endl;

}