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//#pragma GCC optimize("Ofast", "unroll-loops")
//#pragma GCC target("sse", "sse2", "sse3", "ssse3", "sse4")

#include <bits/stdc++.h>

#define all(a) a.begin(),a.end()
#define len(a) (int)(a.size())
#define mp make_pair
#define pb push_back
#define fi first
#define se second

using namespace std;

typedef pair<int, int> pii;
typedef long long ll;
typedef long double ld;
template<class T>
using vec = vector<T>;

template<typename T>
bool umin(T &a, T b) {
    if (b < a) {
        a = b;
        return true;
    }
    return false;
}
template<typename T>
bool umax(T &a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

#ifdef KoRoVa
#define DEBUG for (bool _FLAG = true; _FLAG; _FLAG = false)
#define LOG(...) print(#__VA_ARGS__" ::", __VA_ARGS__) << endl
template <class ...Ts> auto &print(Ts ...ts) { return ((cerr << ts << " "), ...); }
#else
#define DEBUG while (false)
#define LOG(...)
#endif

const int max_n = 1e6 + 11, inf = 1000111222;



const int mod = 1e9 + 7;


inline void inc(int &x, int y) {
    x += y;
    if (x >= mod) {
        x -= mod;
    }
}

inline void dec(int &x, int y) {
    x -= y;
    if (x < 0) {
        x += mod;
    }
}

inline int neg (int x) {
    return x ? mod - x : 0;
}

inline int mul(int x, int y) {
    return (1LL * x * y) % mod;
}

int power(int x, int y) {
    if (y < 0) {
        y += mod - 1;
    }
    if (y == 0) {
        return 1;
    }
    if (y % 2 == 0) {
        return power(mul(x, x), y / 2);
    }
    return mul(x, power(x, y - 1));
}

inline int inv(int x) {
    return power(x, mod - 2);
}


// new mint part


inline int divide (int x, int y) {
    return mul(x, inv(y));
}

struct mint {
#define oper_apply(op, f) mint& operator op (const mint &x) {f(val, x.val); return *this;}
#define oper_apply_const(op, f) mint operator op (const mint &x) const {mint tmp = *this; f(tmp.val, x.val); return tmp;}
#define oper_return(op, f) mint& operator op (const mint &x) {val = f(val, x.val); return *this;}
#define oper_return_const(op, f) mint operator op (const mint &x) const {return mint(f(val, x.val));}

    int val;

    mint(int x = 0) : val(x) {}

    oper_apply(+=, inc);
    oper_apply_const(+, inc);
    oper_apply(-=, dec);
    oper_apply_const(-, dec);
    oper_return(*=, mul);
    oper_return_const(*, mul);
    oper_return(/=, divide);
    oper_return_const(/, divide);
    oper_return(^=, power);
    oper_return_const(^, power);
};



inline mint calc (int n, mint s, mint a) {
    mint res = (s + a) ^ n;
    res -= s ^ n;
    return res;
}

inline mint calc2 (int n, mint s, mint a) {
    mint res = a * mint(n) * ((a + s) ^ (n - 1));
    return res;
}


int main() {
//    freopen("input.txt", "r", stdin);
//    freopen("output.txt", "w", stdout);

    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n, k, m;
    cin >> n >> k >> m;
    vector <mint> p(m + 1);
    mint inv_k = mint(1) / mint(k);
    mint ans = 0;
    mint sum = 0;

    auto add = [&] (int pos, mint val) {
        if (pos <= m) {
            p[pos] += val;
            sum += val * (m - pos);
        }
    };

    add(0, 1);
    add(1, mint(0) - 1);

    mint pref = 0;
    for (int i = 0; i < m; i++) {
        pref += p[i];
        sum -= pref;


//        for (int j = i + 1; j < m; j++) {
//            sum += p[j];
//        }


        mint can = min(k, m - i - 1);
        can *= inv_k;

        if (pref.val) {
            if (can.val == 1) {
                ans += calc2(n, sum, pref);
            } else {
                ans += (calc(n, sum, pref * can) - calc(n, sum, pref)) / (can - 1);
            }
        }
//        LOG(pref.val, (pref * 16).val, sum.val);

        mint val = pref * inv_k;
        add(i + 1, val);
        add(i + k + 1, mint(0) - val);
    }
    cout << ans.val << '\n';
//    LOG((mint(461) / mint(256)).val); 319876872
}

/*
KoRoVa!
*/