#include <cstdio>
#include <iostream>

const int N = int(1e6) + 2;

int n, x;
int a[N];
long long s[N], c[N];
long long ans;

int main()
{
	freopen("input.txt", "rt", stdin);
	freopen("output.txt", "wt", stdout);

	scanf("%d", &n);

	for (int i = 0; i < n; i++)
	{
		scanf("%d", &x);

		a[x]++;
	}

	for (long long i = 1; i <= n; i++)
	{
		c[i] = c[i - 1] + a[i];
		s[i] = s[i - 1] + a[i] * i;
	}

	for (int i = 1; i <= n; i++)
	{
		ans += s[i - 1] * a[i];

		for (int j = i; j <= n; j += i)
		{
			int k = std::min(n, j + i - 1);

			ans += (s[k] - s[j - 1] - (c[k] - c[j - 1]) * j) * a[i];
		}
	}

	std::cout << ans;

	return 0;
}