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#include <bits/stdc++.h>

using namespace std;
#define PB push_back
#define LL long long
#define int LL
#define FOR(i,a,b) for (int i = (a); i <= (b); i++)
#define FORD(i,a,b) for (int i = (a); i >= (b); i--)
#define REP(i,n) FOR(i,0,(int)(n)-1)
#define st first
#define nd second
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())
#define VI vector<int>
#define PII pair<int,int>
#define LD long double

template<class C> void mini(C& a4, C b4) { a4 = min(a4, b4); }
template<class C> void maxi(C& a4, C b4) { a4 = max(a4, b4); }

template<class TH> void _dbg(const char *sdbg, TH h){cerr<<sdbg<<"="<<h<<"\n";}
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
  while(*sdbg!=',')cerr<<*sdbg++;
  cerr<<"="<<h<<","; _dbg(sdbg+1, a...);
}

template<class T> ostream &operator<<(ostream &os, vector<T> V){
  os<<"[";for(auto vv:V)os<<vv<<",";return os<<"]";
} 

template<class L, class R> ostream &operator<<(ostream &os, pair<L,R> P) {
  return os << "(" << P.st << "," << P.nd << ")";
}


#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif

const int mod = 1e9 + 7;

void add_m(int &a, int b) {
    a += b;
    if (a >= mod) a -= mod;
}

void sub_m(int &a, int b) {
    a -= b;
    if (a < 0) a += mod;
}

int mul_m(int a, int b) {
    return a % mod * (b % mod) % mod;
}

int pw(int b, int e) {
    int r = 1; b %= mod;
    for (; e > 0; e >>= 1) {
        if (e & 1) r = mul_m(r, b);
        b = mul_m(b, b);
    }
    return r;
}

int32_t main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n, k, m;
    cin >> n >> k >> m;
    int inv_k = pw(k, mod - 2);

    VI visit(m), visit_psum(m);
    visit[0] = 1;
    visit_psum[0] = 1;
    FOR(s, 1, m - 1) {
        int lo = max(0LL, s - k);
        int window = visit_psum[s - 1];
        if (lo > 0) {
            sub_m(window, visit_psum[lo - 1]);
        }
        visit[s] = mul_m(inv_k, window);
        visit_psum[s] = visit_psum[s - 1];
        add_m(visit_psum[s], visit[s]);
    }

    int ans = 0;
    int safe = max(0LL, m - k);
    if (safe > 0)
        ans = mul_m(n, visit_psum[safe - 1]);

    int cum_exit = 0;
    int surv_prev = 1;
    FOR(s, safe, m - 1) {
        int exit_num = s + k - m + 1;
        int exit_prob = mul_m(exit_num, inv_k);
        add_m(cum_exit, mul_m(visit[s], exit_prob));

        int one_minus_cum = 1;
        sub_m(one_minus_cum, cum_exit);

        int surv_cur = pw(one_minus_cum, n);
        int delta = surv_prev;
        sub_m(delta, surv_cur);

        int contrib = mul_m(mul_m(delta, k), pw(exit_num, mod - 2));
        add_m(ans, contrib);
        surv_prev = surv_cur;
    }

    cout << ans << endl;
}