#include <bits/stdc++.h>
using namespace std;
const int maxn = 2e5 + 5;
const int mod = 1e9 + 7;
const int INF = 0x7fffffff;
long long num[maxn];
long long d[maxn];
int main() {
  long long n, k;
  while (~scanf("%I64d%I64d", &n, &k)) {
    for (int i = 1; i <= n; i++) scanf("%I64d", &num[i]);
    long long d = 0;
    long long pre = 1;
    long long cnt = 2;
    long long nn = n;
    for (int i = 2; i <= n; i++) {
      long long now = num[pre] * (cnt - 2);
      long long sub = (cnt - 1) * (nn - cnt) * num[i];
      if (d + now - sub < k) {
        printf("%d\n", i);
        nn--;
      } else {
        d += now;
        pre = i;
        cnt++;
      }
    }
  }
  return 0;
}
