#include <bits/stdc++.h> #define mp make_pair #define all(vec) vec.begin(),vec.end() using namespace std; using ll=long long; using P=pair<ll,ll>; const ll INF=1LL<<30; const ll LINF=1LL<<60; const double eps=1e-9; const ll MOD=1000000007LL; template<typename T>void chmin(T &a,T b){a=min(a,b);}; template<typename T>void chmax(T &a,T b){a=max(a,b);}; template<typename T>vector<T> make_v(size_t a){return vector<T>(a);} template<typename T,typename... Ts>auto make_v(size_t a,Ts... ts){return vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));} template<typename T,typename V>typename enable_if<is_class<T>::value==0>::type fill_v(T& t,const V& v){t=v;} template<typename T,typename V>typename enable_if<is_class<T>::value!=0>::type fill_v(T& t,const V& v){for(auto &e:t)fill_v(e,v);}; int dx[4]={0,1,0,-1}; int dy[4]={1,0,-1,0}; ll mpow(ll x,ll n){ ll res=1; while(n>0){ if(n&1){ res=res*x%MOD; } n>>=1; x=x*x%MOD; } return res; } vector<ll> f,fi; void comb(int n){ f.resize(n+10); fi.resize(n+10); f[0]=1; for(ll i=1;i<=n;i++){ f[i]=f[i-1]*i; f[i]%=MOD; } fi[n]=mpow(f[n],MOD-2); for(ll i=n-1;i>=0;i--){ fi[i]=fi[i+1]*(i+1LL); fi[i]%=MOD; } } ll ncr(ll n,ll r){ return f[n]*fi[r]%MOD*fi[n-r]%MOD; } int main(){ int n;cin>>n; vector<ll> a(n); for(int i=0;i<n;i++)cin>>a[i]; ll ans=0; comb(n+10); for(ll i=0;i<n;i++){ ans+=a[i]*ncr(n-1,i)%MOD; ans%=MOD; } cout<<ans<<endl; }