#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef unsigned long long ull;

#define N 21
int n;
int a[N];
const int M = 400;
bitset<M + 1>B;

void sol()
{
    for (int i = 1; i <= n; i ++) cin >> a[i];
    ll sum = 0, t = 0;
    for (int i = 1; i <= n; i ++) 
    {
        sum += 1LL * a[i] * i;
        if (a[i]) t = gcd(t, i);
    } 
    if (t == 0) {cout << 1 << '\n'; return ;}
    ll ans = sum / t + 1;
    B = 0; B[0] = 1;
    for (int i = 1; i <= n; i ++)
    {
        int t = i, v = a[i];
        // cout << "GG:" << i << endl;
        while (true)
        {
            if (v == 0 || t > M) break;
            B = B | (B << t);
            // cout << "EE:" << t << endl;
            v --; 
            if (v & 1) {B = B | (B << t); }
            t <<= 1; v /= 2;
        }
    }
    if (sum <= M)
    {
        for (int i = 1; i <= sum; i ++) if (i % t == 0 && !B[i])ans --;
    }
    else if (sum <= 2 * M)
    {
        for (int i = 1; i <= sum; i ++) if (i % t == 0)
        {
            if (i <= M) {if (!B[i])ans --;}
            else {if (!B[sum - i])ans --;}  
        }
    }
    else
    {
        for (int i = 1; i <= M; i ++) if (i % t == 0 && B[i] == 0)ans -= 2;
    }
    cout << ans << '\n';
}

int main()
{
    ios::sync_with_stdio(0); cin.tie(0);
    int T = 1;
    while (cin >> n) sol();
    return 0;
}