#include <bits/stdc++.h>
#define N 1000001
int p[N], dp[N] = {0, 1};
long jaettavia[N];
int main() {
int n;
for (int i = 2; i < N; ++i) {
if (!p[i]) for (int j = i; j < N; j += i) {
if (!p[j]) {
p[j] = i;
}
}
if (p[i / p[i]] == p[i]) {
dp[i] = 0;
} else {
dp[i] = -1 * dp[i / p[i]];
}
}
std::cin >> n;
std::vector<int> luvut(n);
for (int i = 0; i < n; ++i) {
std::cin >> luvut[i];
int l = luvut[i];
for (int j = (int)sqrt(l); j; j--) {
if (l % j == 0) {
jaettavia[j] += 1;
if (j*j != l) {
jaettavia[l/j] += 1;
}
}
}
}
long tulos = 0;
for (int x = 1; x <= 1000000; ++x) {
tulos += dp[x] * (jaettavia[x] * (jaettavia[x] - 1) / 2);
}
std::cout << tulos << std::endl;
}