#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vi = vector<int>;
using vs = vector<string>;
using vl = vector<ll>;
using vb = vector<bool>;
using vvi = vector<vector<int>>;
using vvl = vector<vector<ll>>;
using vvc = vector<vector<char>>;
using pii = pair<int, int>;
template <typename T>
void view(T e) {
  std::cout << e << std::endl;
}
template <typename T>
void view(const std::vector<T>& v) {
  for (const auto& e : v) {
    std::cout << e << " ";
  }
  std::cout << std::endl;
}
template <typename T>
void view(const std::vector<std::vector<T>>& vv) {
  cout << endl;
  int cnt = 0;
  for (const auto& v : vv) {
    cout << cnt << "th : ";
    view(v);
    cnt++;
  }
  cout << endl;
}
const ll mod = 1000000007;
const int inf = 1001001001;
const ll INF = 1001001001001001001;
const int MAX = 10000;
template <class T>
bool chmax(T& a, const T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
bool chmin(T& a, const T b) {
  if (b < a) {
    a = b;
    return 1;
  }
  return 0;
}
ll modpow(ll a, ll p) {
  ll ret = 1;
  while (p) {
    if (p & 1) {
      ret = ret * a % mod;
    }
    a = a * a % mod;
    p >>= 1;
  }
  return ret;
}
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};
int main() {
  int t;
  cin >> t;
  while (t--) {
    int n;
    cin >> n;
    cout << 2 << endl;
    cout << n << " " << n - 1 << endl;
    for (int i = n; i - 2 >= 1; i--) {
      cout << i << " " << i - 2 << endl;
    }
  }
}
