#include <algorithm>
using namespace std;

typedef int int_32;
typedef long long int int_64;

#define INF 1LL<<60
#define MAX_N 505

int_32 N;
int_32 dim[ MAX_N ];
int_64 sol[ MAX_N ][ MAX_N ];

int main() {

    freopen( "podm.in", "r", stdin );
    freopen( "podm.out", "w", stdout );

    int_32 i, j, k, x, y;

    scanf( "%d", &N );
    for( i = 0; i <= N; ++i )
        scanf( "%d", &dim[ i ] );

    for( i = 0; i <= N; ++i )
        for( j = 0; j <= N; ++j )
            sol[ i ][ j ] = INF;

    for( i = 1; i <= N; ++i )
        sol[ i ][ i ] = 0;
    for( i = 1; i < N; ++i )
        sol[ i ][ i+1 ] = (int_64)dim[ i-1 ] * dim[ i ] * dim[ i+1 ];

    for( j = 3; j <= N; ++j )
        for( x = 1, y = j; x <= N && y <= N; ++x, ++y )
            for( k = x; k < y; ++k )
                sol[ x ][ y ] = min( sol[ x ][ y ], sol[ x ][ k ] + sol[ k+1 ][ y ] + (int_64)dim[ x-1 ] * dim[ k ] * dim[ y ] );

//    for( int i = 1; i <= N; ++i ) {
//
//        for( int j = 1; j <= N; ++j )
//            if( sol[ i ][ j ] == INF )
//                printf( "oo " );
//            else
//                printf( "%lld ", sol[ i ][ j ] );
//
//        printf( "\n" );
//    }

    printf( "%lld", sol[ 1 ][ N ] );

    return 0;
}