#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

long factorial(int x){
  long s = 1;
  while ( x > 1) {
    s += x--;
  }
  return s;
}

int solve(int A_size, int* A) {
  //  Return the sum of S(S(A)) modulo 10^9+7.
  int finalsum = 0;
  long b_size = factorial(A_size);
  int *b = malloc(sizeof(int) * b_size);
  int maxfind = 0;
  int bp = 0;

  // for( int i =0; i < A_size; i++){
  //   printf(">> %i , %d\n",i, A[i]);
  // }
  for (int k = 0; k < A_size; k++) {
    for (int i = 0; i < (A_size - k); i++) {
      // b[i+j] = A[i] + A[j];
      int j = i + k;
      maxfind = 0;
      for (int find = i; find <= j; find++){
        maxfind = (A[find] > maxfind)? A[find]: maxfind;
      }
      b[bp] = maxfind;
      // printf(">> %i, %d, %d => %d, %d\n",k, i, j,bp, b[bp]);
      bp++;
    }
  }

  long c_size = factorial(b_size);
  int *c = malloc(sizeof(int) * c_size);
  int cp = 0;
  // printf(">> c_size %ld\n",c_size);

  // for( int i =0; i < b_size; i++){
  //   printf(">> %i , %d\n",i, b[i]);
  // }

  for (int k = 0; k < b_size; k++) {
    for (int i = 0; i < (b_size - k); i++) {
      // b[i+j] = A[i] + A[j];
      int j = i + k;
      maxfind = 0;
      for (int find = i; find <= j; find++){
        maxfind = (b[find] > maxfind)? b[find]: maxfind;
      }
      c[cp] = maxfind;
      // printf(">> %i, %d, %d => %d, %d\n",k, i, j,cp, c[bp]);
      cp++;
    }
  }

  for( int i =0; i < c_size; i++){
    // printf(">> %i , %d\n",i, c[i]);
    finalsum += c[i];
  }

  return finalsum;
}

int main() {
  int n;
  scanf("%i", &n);
  int *A = malloc(sizeof(int) * n);
  for (int a_i = 0; a_i < n; a_i++) {
    scanf("%i",&A[a_i]);
  }
  int result = solve(n, A);
  printf("%d\n", result);
  return 0;
}