#include <bits/stdc++.h>
using namespace std;

#define int long long
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define repi(i,a,b) for(int i=(int)(a);i<(int)(b);i++)
#define all(x) (x).begin(),(x).end()
#define pb push_back
#define mp make_pair
#define mt make_tuple

typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;

const int inf = 1LL<<60;
const int mod = 1e9 + 7;
const double eps = 1e-9;

/*{
  a b c d e
  a+b b+c c+d d+e 
  a+2b+c b+2c+d c+2d+e
  a+3b+3c+d b+3c+3d+e
  a+4b+6c+4b+e
}*/

template<int M>
class Combination
{
public:
  int n;
  vector<int> fac, finv;

  Combination(int n_) : n(n_), fac(n_), finv(n_)
  {
    fac[0] = 1;
    for(int i = 1; i < n; i++) fac[i] = fac[i-1]*i%M;
    finv[n-1] = pow(fac[n-1], M-2);
    for(int i = n-1; i > 0; i--) finv[i-1] = finv[i]*i%M;
  }

  int pow(int a, int b)
  {
    if(b == 0) return 1; 
    return pow(a*a%M, b/2)*(b%2?a:1)%M;
  }

  int C(int a, int b)
  {
    if(b < 0 or a < b) return 0;
    return fac[a]*finv[a-b]%M*finv[b]%M;
  }

  int P(int a, int b)
  {
    if(b < 0 or a < b) return 0;
    return fac[a]*finv[a-b]%M; 
  }

  int H(int a, int b){
    if(a == 0 and b == 0) return 1;
    return C(a+b-1, b);
  }
};

signed main()
{
  Combination<mod> comb(100010);

  int n;
  cin >> n;

  vi a(n);
  rep(i, n) cin >> a[i];

  int ans = 0;
  rep(i, n){
    ans += comb.C(n-1, i) * a[i] % mod;
    ans %= mod;
  }

  cout << ans << endl;

  return 0;
}