#include <bits/stdc++.h>
using namespace std;
int n, k;
long long a, sum = 0, change;
int main() {
  while (cin >> n >> k) {
    int cnt = 0;
    int j = 1;
    for (int i = 1; i <= n; i++) {
      scanf("%I64d", &a);
      change = sum - (i - 1) * (n - i) * a;
      if (change < k) {
        printf("%d\n", j);
        i--;
        n--;
      } else {
        sum += a * (i - 1);
      }
      j++;
    }
  }
  return 0;
}
