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#include<bits/stdc++.h>
bool Mbg;
using namespace std;
#define vec vector
#define pb push_back
#define eb emplace_back
#define SZ(vec) (int)((vec).size())
#define all(vec) (vec).begin(),(vec).end()
#define pii pair<int,int>
#define x first
#define y second
#define mp make_pair
#define exc(expr) if(expr)continue;
#define stop(expr) if(expr)break;
#define ret(expr) if(expr)return;
#define deb(var) std::cerr<<#var<<'='<<(var)<<"; "
#define debl(var) std::cerr<<#var<<'='<<(var)<<";\n"
#define debs(...) std::cerr << "(" << #__VA_ARGS__ << ")=(", deb_out(__VA_ARGS__)
void deb_out() { cerr<<");\n"; }
template <typename H>void deb_out(H h) { std::cerr << h << ");\n"; }
template <typename H, typename...T>void deb_out(H h, T... t){ std::cerr << h << ","; deb_out(t...); }
template<typename T>std::ostream& operator <<(std::ostream& os,const vector<T>& arr){
    if(arr.empty())return os;
    os<<arr[0];
    for(int i=1;i<arr.size();i++)os<<' '<<arr[i];
    return os;
}
#define ins insert
#define era erase
#define lb lower_bound
#define ub upper_bound
#define int long long
#define inf (long long)(1.1e18)
template<typename T>bool Min(T &x,const T &y){return x>y?x=y,1:0;}
template<typename T>bool Max(T &x,const T &y){return x<y?x=y,1:0;}
const int mod=1e9+7;
void Add(int &x,const int &y){x=x+y<mod?x+y:x+y-mod;}
void Dec(int &x,const int &y){x=x>=y?x-y:x-y+mod;}
int fpm(int x,int y){
    int ans=1;for(;y;y>>=1,x=1ll*x*x%mod)if(y&1)ans=1ll*x*ans%mod;return ans;
}

int n,m,k;
int dp[1000010],S[1000010],iv[1000010];
int p[1000010],S1[1000010],S2[1000010];
void work(){
    cin>>n>>k>>m;
    iv[1]=1;
    for(int i=2;i<=1e6;i++){
        iv[i]=(mod-mod/i)*iv[mod%i]%mod;
    }
    dp[0]=1;
    S[0]=1;
    for(int i=1;i<=m;i++){
        dp[i]=(S[i-1]-(i-k-1>=0?S[i-k-1]:0)+mod)*iv[k]%mod;
        S[i]=(S[i-1]+dp[i])%mod;
    }
    p[0]=1;
    S1[0]=1;
    S2[0]=min(m-1,k);
    for(int x=1;x<=m;x++){
        // p[x]:某个人得分第一次不小于x时，游戏还没结束的概率
        p[x]=S1[x-1]*(1-x+mod)+S2[x-1];
        if(x-k-1>=0){
            (p[x]+=S1[x-k-1]*(x-1)+mod-S2[x-k-1])%=mod;
        }
        p[x]%=mod;
        (p[x]*=iv[k])%=mod;

        S1[x]=(S1[x-1]+dp[x])%mod;
        S2[x]=(S2[x-1]+dp[x]*min(m-1,x+k))%mod;
    }
    int ans=0;
    for(int x=0;x<m;x++){
        int a=p[x+1]*fpm(p[x],mod-2)%mod;
        if(a==1){
            (ans+=a*n%mod*fpm(p[x],n-1)%mod*dp[x])%=mod;
        }else{
            (ans+=(fpm(a,n)-1+mod)*fpm(a-1+mod,mod-2)%mod*fpm(p[x],n-1)%mod*dp[x])%=mod;
        }
    }
    cout<<ans<<'\n';
}
bool Med;
signed main(){
    ios::sync_with_stdio(0),
    cin.tie(0),cout.tie(0);
    int T=1;while(T--)work();
    // cerr<<"Time: "<<clock()<<" ms;\n";
    // cerr<<"Memory: "<<abs(&Med-&Mbg)/1024.0/1024.0<<" MiB.\n";
}
/*
- CONTINUE, NON-STOPPING, FOR THE FAITH
- START TYPING IF YOU DON'T KNOW WHAT TO DO
- STOP TYPING IF YOU DON'T KNOW WHAT YOU'RE DOING
*/