#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, k, a[2 * 100000 + 100];
  scanf("%d%d", &n, &k);
  for (int i = 1; i <= n; i++) scanf("%d", &a[i]);
  int c = 0;
  long long sum = 0;
  for (int i = 2; i <= n; i++) {
    if ((sum - (long long)(i - c - 1) * (n - c - (i - c)) * a[i]) <
        (long long)k) {
      c++;
      printf("%d\n", i);
    } else
      sum += (i - 1 - c) * a[i];
  }
  return 0;
}
