#include <iostream>
#include <unordered_map>
using namespace std;
int primes[] = { 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137,
139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293,
307, 311, 313, 317, 331, 337, 347, 349, 353, 359, 367, 373, 379, 383, 389, 397, 401, 409, 419, 421, 431, 433, 439, 443, 449, 457, 461, 463, 467,
479, 487, 491, 499, 503, 509, 521, 523, 541, 547, 557, 563, 569, 571, 577, 587, 593, 599, 601, 607, 613, 617, 619, 631, 641, 643, 647, 653, 659,
661, 673, 677, 683, 691, 701, 709, 719, 727, 733, 739, 743, 751, 757, 761, 769, 773, 787, 797, 809, 811, 821, 823, 827, 829, 839, 853, 857, 859,
863, 877, 881, 883, 887, 907, 911, 919, 929, 937, 941, 947, 953, 967, 971, 977, 983, 991, 997 };
int main()
{
int amo;
cin >> amo;
int num;
int prime, b;
unsigned long sum = 0;
unordered_map<int, unsigned int> nums;
for (int i = 0; i < amo; i++) {
cin >> num;
//num = (rand() % 100) + 1;
auto x = nums.find(num);
if (x == nums.end()) { nums[num] = 1; }
else { nums[num]++; }
}
int ramo = nums.size();
unsigned long* d = new unsigned long[ramo * 3]();
unsigned long* counts = new unsigned long[ramo]();
/*long d[500];
for (int i = 0; i < 500; i++) { d[i] = 0; }*/
if (nums.find(1) != nums.end()) { sum = ((nums[1] - 1) * nums[1]) / 2; }
int i = 0;
for (auto x = nums.begin(); x != nums.end(); ++x) {
num = x->first;
counts[i] = x->second;
int ib = i * 3;
for (int p = 0, ic = ib; p < 168; p++) {
prime = primes[p];
if (num < prime) break;
b = p & 63;
if ((num % prime) == 0) {
d[ic] |= (1 << b);
}
if (b == 63) { ic++; }
}
int jb;
for (int j = 0; j < i; j++) {
jb = j * 3;
if (((d[ib] & d[jb]) == 0) &&
((d[ib + 1] & d[jb + 1]) == 0) &&
((d[ib + 2] & d[jb + 2]) == 0)) {
sum += (counts[i] * counts[j]);
}
}
i++;
}
cout << sum << endl;
}
