#include using namespace std; const int M = 1000000007; int main() { cin.tie(0); ios::sync_with_stdio(0); int n; cin >> n; vector a(n); for (int i = 0; i < n; ++i) { cin >> a[i]; } vector> mid(n + 1); for (int i = 1; i <= n; ++i) { mid[i] = vector(i); } for (int i = 0; i < n; ++i) { priority_queue lq; priority_queue, greater> uq; mid[i + 1][i] = a[i]; if (i == n - 1) continue; mid[i + 2][i] = min(a[i], a[i + 1]); lq.push(min(a[i], a[i + 1])); uq.push(max(a[i], a[i + 1])); for (int j = i + 2; j < n; ++j) { if (lq.top() <= a[j] && a[j] <= uq.top()) { if (lq.size() == uq.size()) lq.push(a[j]); else uq.push(a[j]); } else if (lq.top() > a[j]) { lq.push(a[j]); while (lq.size() > uq.size() + 1) { uq.push(lq.top()); lq.pop(); } } else { uq.push(a[j]); while (uq.size() > lq.size()) { lq.push(uq.top()); uq.pop(); } } mid[j + 1][i] = lq.top(); } } long long ans = 0; for (int i = 1; i <= n; ++i) { vector sl(n / i + 1), sr(n / i + 1); vector ml(n / i + 1), mr(n / i + 1); for (int j = 0; j < n / i; ++j) { sl[j + 1] = sl[j] + mid[(j + 1) * i][j * i] * (long long)i; ml[j + 1] = max(ml[j], sl[j + 1]); } for (int j = 0; j < n / i; ++j) { sr[j + 1] = sr[j] + mid[n - j * i][n - (j + 1) * i] * (long long)i; mr[j + 1] = max(mr[j], sr[j + 1]); } for (int j = 0; j < n / i; ++j) { ans = max(ans, ml[j] + mr[n / i - j]); } } cout << ans << '\n'; return 0; }