#include <bits/stdc++.h>
using namespace std;
#define int              long long int
#define double           long double
#define print(a)         for(auto x : a) cout << x << " "; cout << endl


const int M = 1000000007;
const int N = 3e5+9;
const int INF = 2e9+1;
const int LINF = 2000000000000000001;

inline int power(int a, int b, int mod=M) {
    int x = 1;
    a %= mod;
    while (b) {
        if (b & 1) x = (x * a) % mod; 
        a = (a * a) % mod;
        b >>= 1;
    }
    return x;
}


//_ ***************************** START Below *******************************




vector<int> a;

int consistency(int n){

	vector<vector<int>> dp(n, vector<int>(n, 0));
	
	for(int gap=0; gap<n; gap++){
	    for(int i=0,j=gap; j<n; i++, j++){
	    	
	        if(gap == 0){
	            int left = i-1>=0 ? a[i-1] : 1;
	            int right = j+1 < n ? a[j+1] : 1;
	            dp[i][j] = left * a[i] * right;
	        }
	        else{
	            
	            for(int k=i; k<=j; k++){
	                int left = i-1>=0 ? a[i-1] : 1;
	                int right = j+1 < n ? a[j+1] : 1;
	                int cost = left * a[k] * right;
	                if(k-1>=i) cost += dp[i][k-1];
	                if(k+1<=j) cost += dp[k+1][j];
	                dp[i][j] = max(dp[i][j], cost);
	            }
	        }
	    }
	}
	
	
	return dp[0][n-1];

}















int practice(int n){


    return 0;
}





void solve() {
    
    int n;
    cin>> n;
    
    a.resize(n);
    for(int i=0; i<n; i++) cin >> a[i];
    
    cout << consistency(n) << endl;


}





int32_t main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }

    return 0;
}