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