#include <cstdio>
#include <iostream>

#define dbg(x) cerr << #x << ": " << x << endl;
#define NMAX 100005
using namespace std;

long long nrBad;
int v[NMAX], maxx;
bool ciur[NMAX * 10], exist[NMAX * 10];

int main(){
	freopen("pairs.in", "r", stdin);
	freopen("pairs.out", "w", stdout);
	int n;
	cin >> n;

	for(int i = 1; i <= n; ++i){
		cin >> v[i];
		maxx = max(maxx, v[i]);
		exist[v[i]] = 1;
	}

	long long nrPerechiNonBune = 0;
	for(int i = 2; i <= maxx / 2; ++i)
		if(ciur[i] == 0){
			long long cnt = 0;
			for(int j = i; j <= maxx; j += i)
			{
				if(exist[j] == 1)
					++cnt;
				ciur[j] = 1;
			}

			nrPerechiNonBune += ((cnt - 1) * cnt) / 2;
		}
	
	long long rez = (1LL * (n - 1) * n) / 2 - nrPerechiNonBune;
	cout << rez << '\n';
	return 0;
}