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#include <bits/stdc++.h>
using ll = long long;
using ld = long double;
using ull = unsigned long long;
using namespace std;
template <class T>
using Ve = vector<T>;
#define ALL(v) (v).begin(), (v).end()
#define pii pair<ll, ll>
#define rep(i, a, b) for(ll i = (a); i <= (b); ++i)
#define per(i, a, b) for(ll i = (a); i >= (b); --i)
#define pb push_back
bool Mbe;
ll read() {
    ll x = 0, f = 1; char ch = getchar();
    while(ch < '0' || ch > '9') {if(ch == '-') f = -1; ch = getchar();}
    while(ch >= '0' && ch <= '9') x = x * 10 + ch - '0', ch = getchar();
    return x * f;
}
void write(ll x) {
    if(x < 0) putchar('-'), x = -x;
    if(x > 9) write(x / 10);
    putchar(x % 10 + '0');
}
const ll N = 1e6 + 9, Mod = 1e9 + 7;
ll n, K, m, f[N], g[N], h[N], sum[N], iK;
ll pw(ll x, ll p) {
    ll res = 1;
    while(p) {
        if(p & 1) res = res * x % Mod;
        x = x * x % Mod, p >>= 1;
    }
    return res;
}
ll calc(ll x, ll y) {
    if(x == y) return n * pw(x, n - 1) % Mod;
    return (pw(x, n) - pw(y, n) + Mod) % Mod * pw((x - y + Mod) % Mod, Mod - 2) % Mod;
}
bool Med;
int main() {
    cerr << fabs(&Med - &Mbe) / 1048576.0 << "MB\n";
    n = read(), K = read(), m = read();
    f[0] = 1;
    sum[0] = 1, iK = pw(K, Mod - 2);
    rep(i, 1, m) {
        ll l = max(0ll, i - K), r = i - 1;
        f[i] = (sum[r] - (l ? sum[l - 1] : 0) + Mod) * iK % Mod;
        sum[i] = (sum[i - 1] + f[i]) % Mod;
    }
    rep(i, 0, m - 1) {
        ll l = m - i, r = K;
        if(l <= r) h[i] = (r - l + 1) * iK % Mod * f[i] % Mod;
    }
    rep(i, 1, m) h[i] = (h[i - 1] + h[i]) % Mod;
    g[0] = 1;
    rep(i, 1, m) g[i] = (1 - h[i - 1] + Mod) % Mod;
    ll ans = 0;
    rep(i, 0, m - 1) ans = (ans + f[i] * calc(g[i + 1], g[i])) % Mod;
    write(ans), putchar('\n');
    cerr << "\n" << clock() * 1.0 / CLOCKS_PER_SEC * 1000 << "ms\n";
    return 0;
}