Problem:
Score : 700 points

Problem Statement

We have N gemstones labeled 1 through N.

You can perform the following operation any number of times (possibly zero).

Select a positive integer x, and smash all the gems labeled with multiples of x.

Then, for each i, if the gem labeled i remains without getting smashed, you will receive a_i yen (the currency of Japan).
However, a_i may be negative, in which case you will be charged money.

By optimally performing the operation, how much yen can you earn?

Constraints

All input values are integers.

1 \leq N \leq 100

|a_i| \leq 10^9

Input

Input is given from Standard Input in the following format:

N
a_1 a_2 ... a_N

Output

Print the maximum amount of money that can be earned.

Sample Input 1

6
1 2 -6 4 5 3

Sample Output 1

12

It is optimal to smash Gem 3 and 6.

Sample Input 2

6
100 -100 -100 -100 100 -100

Sample Output 2

200

Sample Input 3

5
-1 -2 -3 -4 -5

Sample Output 3

0

It is optimal to smash all the gems.

Sample Input 4

2
-1000 100000

Sample Output 4

99000

Solution in Ruby (2.3.3) (judge verdict: Wrong Answer)

# Your code here!
n=gets.to_i

array=gets.split.map(&:to_i)

array2=[]
i=0
n.times{
    array2<<[i+1,array[i]]
    i+=1
    
    
}



sum=0
hhh=0
n.times{
    sum+=array[hhh]
    
    hhh+=1
    
    
}


s=n/2

min=10**11
jj=1

n.times{
    array3=array2.select{  |ss|  ss[0]%jj==0}
   nn=0
   kk=0
   array3.length.times{
       kk+=array3[nn][1]
       nn+=1
       
       
   }
   
   if kk<min
       
       min=kk
      end
   
   
    
    jj+=1
    
    
    
    
    
}

puts sum-min