#include <bits/stdc++.h>
using namespace std;
int n, a[1000005], f = 1, inv[1000005], tot[1000005], tut[1000005], all, ans;
int fe(int x, int y) {
  if (y == 0) return 1;
  if (y == 1) return x;
  int res = fe(x, y / 2);
  res = 1ll * res * res % 1000000007;
  if (y & 1) res = 1ll * res * x % 1000000007;
  return res;
}
int main() {
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) {
    scanf("%d", &a[i]);
  }
  for (int i = 1; i <= n; i++) {
    inv[i] = fe(i, 1000000007 - 2);
    f = 1ll * f * i % 1000000007;
  }
  sort(a + 1, a + 1 + n);
  int cnt = 0;
  for (int i = 1; i <= n; i++) {
    ++cnt;
    while (i + 1 <= n && a[i] == a[i + 1]) {
      tot[cnt]++;
      i++;
    }
    tut[cnt] = a[i];
    tot[cnt]++;
  }
  all = n;
  for (int i = 1; i < cnt; i++) {
    ans = (ans + 1ll * tut[i] * tot[i] * inv[all] % 1000000007) % 1000000007;
    all -= tot[i];
  }
  printf("%d", 1ll * ans * f % 1000000007);
}
