#include <stdio.h>
#define MOD ((long long)(1e9) + 7)
typedef long long ll;

ll fact[100005], finv[100005], inv[100005];

void init()
{
    fact[0] = fact[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;

    for (ll i = 2; i < 100005; i++) {
        fact[i] = fact[i - 1] * i % MOD;
        inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
        finv[i] = finv[i - 1] * inv[i] % MOD;
    }

    return;
}

long long com(int n, int k)
{
    if (n < k) {
        return 0;
    }
    
    if (n < 0 || k < 0) {
        return 0;
    }
    
    return fact[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}

int main()
{
    init();
    
    ll n;
    ll a[100005];
    ll ans = 0;

    scanf("%lld", &n);
    for (int i = 1; i <= n; i++) {
        scanf("%lld", &a[i]);
    }

    ans = a[1] + a[n];
    ans = ans % MOD;
    for (int r = 2; r < n; r++) {
        ans = ans + a[r] * com(n - 1, r - 1);
        ans % MOD;
    }

    printf("%lld\n", ans);

    return 0;
}