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#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
//mt19937 mrand(random_device{}());
const ll mod=1000000007;
//int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
int gcd(int a,int b) { return b?gcd(b,a%b):a;}
// head

const int N=1e6+5;

#define INF 0x3f3f3f3f

template<class T> inline void read(T &x) {
    x=0; int c=getchar(),f=1;
    for (;!isdigit(c);c=getchar()) if (c==45) f=-1;
    for (;isdigit(c);c=getchar()) (x*=10)+=f*(c-'0');
}

ll buff[N];

int main() {
    ll n,k,m;
    scanf("%lld%lld%lld",&n,&k,&m);
    ll ik=powmod(k,mod-2);
    ll game_lives_prob=1,ans=0;
    ll curr_sum=0;
    rep(i,0,m) {
        ll walk_prob;
        if (i==0) walk_prob=1;
        else walk_prob=(curr_sum*ik)%mod;
        curr_sum=(curr_sum+walk_prob)%mod;
        if (i>=k) curr_sum=(curr_sum-buff[i%k]+mod)%mod;
        buff[i%k]=walk_prob;
        ll finish_ways=i+k-m+1;
        if (finish_ways<=0) ans=(ans+n*walk_prob%mod)%mod;
        else {
            ll game_ends_prob=(walk_prob*finish_ways%mod)*ik%mod;
            ll game_lives_prob_new=(game_lives_prob-game_ends_prob+mod)%mod;
            ll diff=(powmod(game_lives_prob,n)-powmod(game_lives_prob_new,n)+mod)%mod;
            ans=(ans+(diff*k%mod)*powmod(finish_ways,mod-2)%mod)%mod;
            game_lives_prob=game_lives_prob_new;
        }
    }
    printf("%lld\n",ans);
}