#include<bits/stdc++.h>
using namespace std;

int main() { 
    //cout<<"1";
    int n,i,j;
    cin >> n;
    //cout<<"a";
    long long int res[1000003];
    res[1]=1;
    for(i=2,j=1;i<1000001;i++)
    {
        if(i%2==0)
        {
            res[i]=i+res[j];
            j++;
        }
        else
            res[i]=i+1;
    }
    //cout<<"b";
    unsigned long long int sum=0;
    vector <long long> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
        sum+=res[a[i]];
    }
  cout<<sum;
    /* Enter your code here. Print output to STDOUT */   
 
    return 0;
}