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#include <bits/stdc++.h>
#define FOR(i,p,k) for(int i=(p);i<=(k);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define RFOR(i,p,n) for(int i=(p);i>=(n);--i)
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
#define ssize(x) int((x).size())
#define fi first
#define se second
#define V vector
#define pb push_back
#define eb emplace_back
#define C const
#define gc getchar_unlocked
#define pc putchar_unlocked
#define pn putchar_unlocked('\n')
using namespace std;
typedef long long ll;
typedef __int128_t lll;
typedef V<int> vi;
typedef V<ll> vll;
typedef const int ci;
typedef const ll cll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<ll, int> pli;
typedef pair<int, ll> pil;
void chmin(auto &a, auto b){a=min(a,b);}
void chmax(auto &a, auto b){a=max(a,b);}
ci inf = 2.1e9;
cll infll = 4.5e18;
int I(){
    int z;
    int c = gc();
    while(c < '0' || c > '9') c = gc();
    for(z = 0; c >= '0' && c <= '9'; c = gc()) z = 10*z+c-'0';
    return z;
}
void O(int a){
    static int tab[20];
    int it = 0;
    do{
        tab[it++] = int('0'+a%10);
    } while(a /= 10);
    while(it) pc(tab[--it]);
}

ci mod = int(1e9)+7;
int add(ci a, ci b){
    return a+b<mod ? a+b : a+b-mod;
}
int sub(ci a, ci b){
    return a<b ? a-b+mod : a-b;
}
int mul(ci a, ci b){
    return int(ll(a)*b%mod);
}
int pot(int a, int b = mod-2){
    int ret = 1;
    for(; b; b /= 2, a = mul(a, a)) if(b&1) ret = mul(ret, a);
    return ret;
}

int gownogowno(ci a, ci b, ci n){
    if(a == b) return mul(n, pot(a, n-1));
    ci licz = sub(pot(a, n), pot(b, n));
    ci mian = sub(a, b);
    return mul(licz, pot(mian));
}

ci odw2 = pot(2);
int po2(ci n){
    return mul(mul(n, n-1), odw2);
}

int gownogownolin(ci a, ci b, ci n){
    if(n == 1) return 0;
    if(a == 0) return pot(b, n-2);
    if(a == b) return mul(po2(n), pot(a, n-2));
    ci licz = add(sub(mul(n-1, pot(a, n+1)), mul(mul(b, n), pot(a, n))), mul(a, pot(b, n)));
    ci mian = mul(a, pot(sub(a, b), 2));
    return mul(licz, pot(mian));
}

void answer(){
    ci n = I();
    ci k = I();
    ci m = I();
    ci odwk = pot(k);

    vi odw(m, 0), pref_odw(m+1, 0);
    REP(i, m){
        if(i) odw[i] = mul(sub(pref_odw[i], pref_odw[max(0, i-k)]), odwk);
        else odw[i] = 1;
        pref_odw[i+1] = add(pref_odw[i], odw[i]);
    }

    vi s(m);
    REP(i, m) s[i] = mul(max(k-m+i+1, 0), odwk);

    vi r(m, 0), pref_r(m+1, 0);
    REP(i, m){
        if(i) r[i] = add(odw[i], mul(sub(pref_r[i], pref_r[max(0, i-k)]), odwk));
        else r[i] = 0;
        pref_r[i+1] = add(pref_r[i], r[i]);
    }

    vi conaj_s(m+1, 0);
    RFOR(i, m-1, 0) conaj_s[i] = add(conaj_s[i+1], mul(s[i], odw[i]));

    vi dupa(m);
    REP(i, m) dupa[i] = add(r[i], odw[i]);

    vi pref_dupa(m+1, 0);
    REP(i, m) pref_dupa[i+1] = add(pref_dupa[i], dupa[i]);

    vi conaj_xd(m+1, 0);
    FOR(i, 1, m){
        conaj_xd[i] = add(conaj_xd[i-1], mul(dupa[i-1], min(k, m-i)));
        conaj_xd[i] = sub(conaj_xd[i], sub(pref_dupa[i-1], pref_dupa[max(0, i-1-k)]));
    }
    FOR(i, 1, m) conaj_xd[i] = mul(conaj_xd[i], odwk);

    int wyn = 0;
    REP(i, m){
        int tmp = 0;
        tmp = add(tmp, mul(dupa[i], gownogowno(conaj_s[i], conaj_s[i+1], n)));
        tmp = add(tmp, mul(mul(conaj_xd[i+1], odw[i]), gownogownolin(conaj_s[i+1], conaj_s[i], n)));
        tmp = add(tmp, mul(mul(conaj_xd[i], odw[i]), gownogownolin(conaj_s[i], conaj_s[i+1], n)));
        wyn = add(wyn, mul(tmp, s[i]));
    }
    O(wyn), pn;
}

int main(){
    int tt = 1;
    while(tt--) answer();
}