#include <bits/stdc++.h>
using namespace std;
template <typename T> using min_priority_queue = priority_queue<T,vector<T>,greater<T>>;

template<typename T>
void outvec(vector<T> &v){
    bool b = false;
    for(auto i : v){
        if(b) cout << " ";
        else b = true;
        cout << i;
    }
    cout << endl;
}

template<typename T>
void invec(vector<T> &v){
    for(auto &i : v){
        cin >> i;
    }
}

template <typename T>
bool chmin(T &a, const T& b) {
    if (a > b) {
        a = b;  // aをbで更新
        return true;
    }
    return false;
}

template <typename T>
bool chmax(T &a, const T& b) {
    if (a < b) {
        a = b;  // aをbで更新
        return true;
    }
    return false;
}

template <typename T>
T exEuclid(T a, T b, T &x, T &y){
    T d = a;
    if(b != 0){
        d = exEuclid(b, a%b, y, x);
        y -= (a/b)*x;
    }
    else{
        x = 1;
        y = 0;
    }
    //cout << a << " * " << x << " + " << b << " * " << y << " = " << d << endl;
    return d;
}

int64_t mod;
struct modint{
    int64_t n;
    int64_t p;

    modint(){
        n = 0;
        p = mod;
    }
    modint(int64_t a){
        if(a <= -mod) a %= mod;
        else if(a >= mod) a %= mod;
        if(a < 0) a += mod;
        n = a;
        p = mod;
    }
    modint(int64_t a, int64_t q){
        if(a <= -q) a %= q;
        else if(a >= q) a %= q;
        if(a < 0) a += q;
        n = a;
        p = q;
    }

    modint pow(int64_t a){
        if(a <= 1-p) a %= p-1;
        else if(a >= p-1) a %= p-1;
        if(a < 0) a += p-1;

        modint rtn;
        if(n == 0) {
            rtn.n = 0;
            return rtn;
        }
        if(n == 1) {
            rtn.n = 1;
            return rtn;
        }
        if(a == 0) {
            rtn.n = 1;
            return rtn;
        }
        if(a == 1) {
            rtn.n = n;
            return rtn;
        }

        int64_t b = a/2;
        int64_t c = a%2;
        rtn = pow(b);
        rtn *= rtn;
        if(c){
            rtn *= modint(n);
        }
        return rtn;
    }

    bool operator==(modint other){
        return n == other.n && p == other.p;
    }
    bool operator!=(modint other){
        return !(n == other.n && p == other.p);
    }

    modint operator+(modint other){
        modint rtn(n+other.n, p);
        return rtn;
    }
    modint operator-(modint other){
        modint rtn(n-other.n, p);
        return rtn;
    }
    modint operator*(modint other){
        modint rtn(n*other.n, p);
        return rtn;
    }
    modint operator/(modint other){
        int64_t x, y, d;
        d = exEuclid(other.n, p, x, y);
        int64_t rtn = x*n;
        if(d > 1) rtn /= d;
        return modint(rtn);
    }

    void operator+=(modint other){
        n += other.n;
        if(n >= p) n %= p;
    }
    void operator-=(modint other){
        n -= other.n;
        if(n < 0) n += p;
    }
    void operator*=(modint other){
        n *= other.n;
        if(n >= p) n %= p;
    }
    void operator/=(modint other){
        int64_t x, y, d;
        d = exEuclid(other.n, p, x, y);
        n *= x;
        if(d > 1) n /= d;
        if(n <= p || p <= n) n %= p;
        if(n < 0) n += p;
        return;
    }
    void operator++(){
        n++;
        if(n == p) n = 0;
        return;
    }
    void operator--(){
        n--;
        if(n == -1) n = p-1;
        return;
    }
};

vector<modint> fact_mod_v;
vector<modint> inv_fact_mod_v;

modint comb_mod(int64_t n, int64_t m){
    if(n < 0 || m < 0 || m > n) return 0;
    modint rtn = fact_mod_v[n]*inv_fact_mod_v[m]*inv_fact_mod_v[n-m];
    return rtn;
}

modint comb_mod_small(int64_t n, int64_t m){
    if(m < mod){
        return comb_mod(n%mod, m);
    }
    return comb_mod_small(n/mod, m/mod)*comb_mod(n%mod, m%mod);
}

void init_fact(int64_t n){
    fact_mod_v.resize(n+1,0);
    inv_fact_mod_v.resize(n+1,0);
    for(int64_t i = 0; i <= n; i++){
        if(i == 0){
            fact_mod_v[i] = modint(1);
        }
        else{
            fact_mod_v[i] = modint(i*fact_mod_v[i-1].n);
        }
        //cout << i << endl;
    }
    for(int64_t i = min(n, mod-1); i >= 0; i--){
        if(i == min(n, mod-1)){
            inv_fact_mod_v[i] = modint(fact_mod_v[i]).pow(-1);
        }
        else{
            inv_fact_mod_v[i] = modint(inv_fact_mod_v[i+1].n*(i+1));
        }
        //cout << i << endl;
    }
}

template <typename T>
struct monoid_plus{
    T val;

    monoid_plus(){
        ;
    }

    monoid_plus(T x){
        val = x;
    }

    monoid_plus e(){
        return monoid_plus(0);
    }

    monoid_plus operator*(monoid_plus other){
        return monoid_plus(val + other.val);
    }
};

template <typename monoid>
struct segtree{
    int sz;
    vector<monoid> dat;

    segtree(){
        ;
    }
    
    segtree(int n){
        sz = 1;
        while(sz <= n) sz *= 2;

        dat.resize(2*sz-1, monoid().e());
    }

    void update(int k, monoid a){
        k += sz-1;
        dat[k] = a;
        while(k > 0){
            k = (k-1)/2;
            dat[k] = dat[2*k+1]*dat[2*k+2];
        }
    }

    void plus(int k, monoid a){
        update(k, get(k, k+1)*a);
    }

    //[a,b)
    monoid get(int a, int b){
        return sub_get(a, b, 0, 0, sz);
    }

    monoid sub_get(int a, int b, int k, int l, int r){
        if(r <= a || b <= l) return monoid().e();
        if(a <= l && r <= b) return dat[k];
        monoid vl = sub_get(a, b, 2*k+1, l, (l+r)/2);
        monoid vr = sub_get(a, b, 2*k+2, (l+r)/2, r);
        return vl*vr;
    }
};

void yn(bool b){
    if(b) cout << "Yes" << endl;
    else cout << "No" << endl;
}

bool debug;
bool randomInput;
bool debugOutput;
int numOfTestCase;

using ans_type = int;

void input(){
    if(numOfTestCase > 1){
        ;
    }

    if(randomInput){
        
    }
    else{
        
    }
    return;
}

void output_input(){
    ;
}

ans_type calc(){
    mod = 1'000'000'007;
    int N, S, K;
    cin >> N >> S >> K;
    int M = S - N * (N - 1) / 2 * K;
    if(M < 0){
        cout << 0 << endl;
        return 0;
    }

    vector<vector<int64_t>> dp(N+1, vector<int64_t>(M+1, 0));
    dp[0][0] = 1;
    //int cnt = 0;
    for(int i = 0; i < N; i++){
        for(int j = 0; j <= M; j++){
            for(int k = 0; j+k <= M; k += N-i){
                dp[i+1][j+k] += dp[i][j];
                //cnt++;
            }
        }

        for(int j = 0; j <= M; j++) dp[i+1][j] %= mod;
    }

    cout << dp[N][M] << endl;
    //cout << cnt << endl;
    /*for(auto i : dp){
        for(auto j : i){
            cout << j.n << " ";
        }
        cout << endl;
    }*/
    return ans_type();
}

ans_type calc_simple(){
    return ans_type();
}

void output(ans_type ans){
    return;
}

int main(){
    debug = 0;
    randomInput = 0;
    debugOutput = 0;
    numOfTestCase = 1;
    srand(time(NULL));
    cout << fixed << setprecision(12);
    
    if(numOfTestCase == 0) cin >> numOfTestCase;

    if(debug){
        for(int i = 0; i < numOfTestCase; i++){
            input();
            ans_type ans = calc();
            ans_type ansSimple = calc_simple();
            if(ans != ansSimple){
                output_input();
                output(ans);
                output(ansSimple);
            }
        }
    }
    else{
        for(int i = 0; i < numOfTestCase; i++){
            input();
            output(calc());
        }
    }

    return 0;
}