#include<stdio.h>
#include<stdlib.h>
#include<math.h>

typedef long long int int64;

#define MAX(a,b) ((a)>(b)?(a):(b))
#define MIN(a,b) ((a)<(b)?(a):(b))
#define ABS(a) ((a)>(0)?(a):-(a))

const int mod=1000000007;

int inv(int a){
  int t=1;
  while(a>1){
    t=(int64)t*(mod-mod/a)%mod;
    a=mod%a;
  }
  return t;
}

void run(void){
  int n;
  scanf("%d",&n);
  int ans=0;
  int comb=1;
  for(int i=0;i<n;i++){
    int a;
    scanf("%d",&a);
    ans=(ans+(int64)comb*a)%mod;
    comb=(int64)comb*(n-1-i)%mod*inv(i+1)%mod;
  }
  printf("%d\n",ans);
}

int main(void){
  run();
  return 0;
}