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#include <fstream>
#include <vector>
#define VAL 1005
#define DIM 1000005
using namespace std;
ifstream fin("pairs.in");
ofstream fout("pairs.out");
int N, i, j, nr;
int d[VAL], K, cnt;
int ANS;
bool ok[VAL];
vector<int> prim;
vector<int> :: iterator it;
void Sieve()
{
for (i=2; i<VAL; i++)
{
if (ok[i]==false)
{
prim.push_back(i);
for (j=i*i; j<VAL; j+=i)
ok[j]=true;
}
}
}
int main()
{
fin >> N;
Sieve();
for (cnt=1; cnt<=N; cnt++)
{
fin >> nr;
K=0;
for (it=prim.begin(); it!=prim.end() && (*it)*(*it)<=nr; it++)
{
if (nr % (*it)==0)
{
d[K++]=*it;
while (nr % (*it)==0)
nr/=*it;
}
if (nr==1)
break;
}
if (nr>1)
d[K++]=nr;
for (i=1; i<(1 << K); i++)
{
nr=0;
for (j=0; j<K; j++)
if ((i & (1 << j))!=0)
nr++;
if (nr % 2==1)
ANS++;
else
ANS--;
}
}
fout << ANS << '\n';
fin.close();
fout.close();
return 0;
}