#include <bits/stdc++.h>

using namespace std;
#define ll long long
#define pii pair<int, int>
#define ld long double
#define all(a) (a).begin(), (a).end()

const int MAXN = 2e3 + 100;
int a[MAXN][MAXN];

int id;

void col24(int i, int j) {
    a[i][j] = a[i + 1][j] = a[i][j + 1] = a[i + 1][j + 2] = id;
    ++id;
    a[i + 1][j + 1] = a[i][j + 2] = a[i][j + 3] = a[i + 1][j + 3] = id;
    ++id;
}

void col42(int i, int j) {
    a[i][j] = a[i][j + 1] = a[i + 1][j] = a[i + 2][j + 1] = id;
    ++id;
    a[i + 1][j + 1] = a[i + 2][j] = a[i + 3][j] = a[i + 3][j + 1] = id;
    ++id;
}

void col33(int i, int j) {
    a[i][j] = a[i + 1][j + 1] = a[i + 2][j] = a[i + 2][j + 1] = id;
    ++id;
    a[i + 1][j] = a[i][j + 1] = a[i][j + 2] = a[i + 1][j + 2] = id;
    ++id;
}

void coli33(int i, int j) {
    a[i + 1][j] = a[i + 2][j] = a[i + 1][j + 1] = a[i + 2][j + 2] = id;
    ++id;
    a[i][j + 1] = a[i][j + 2] = a[i + 1][j + 2] = a[i + 2][j + 1] = id;
    ++id;
}

int sn;

void print() {
    cout << id - 1 << "\n";
    for (int i = 0; i < sn; ++i) {
        for (int j = 0; j < sn; ++j) {
            cout << a[i][j];
            if (j != sn - 1) {
                cout << " ";
            }
        }
        cout << "\n";
    }
}

void solve() {
    int n;
    cin >> n;
    sn = n;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < n; ++j) {
            a[i][j] = 0;
        }
    }
    id = 1;
    if (n % 4 == 0) {
        for (int i = 0; i < n; i += 2) {
            for (int j = 0; j < n; j += 4) {
                col24(i, j);
            }
        }
        print();
        return;
    }
    if (n % 4 == 2) {
        for (int i = 0; i < n; i += 2) {
            for (int j = 0; j < n - 2; j += 4) {
                col24(i, j);
            }
        }
        for (int i = 0; i < n - 2; i += 4) {
            col42(i, n - 2);
        }
        print();
        return;
    }
    if (n % 4 == 3) {
        for (int i = 0; i < n - 3; i += 4) {
            col24(n - 2, i);
            col42(i, n - 2);
        }
        coli33(n - 3, n - 3);
        n -= 2;
    }
    if (n < 4) {
        print();
        return;
    }
    int l = 0;
    int r = n;
    while (r - l > 5) {
        col33(l, l);
        for (int i = l + 3; i + 4 <= r; i += 4) {
            col24(l, i);
            col42(i, l);
        }
        for (int i = l; i + 4 <= r; i += 4) {
            col24(r - 2, i);
            if (i != r - 5) {
                col42(i, r - 2);
            }
        }
        coli33(r - 5, r - 3);
        l += 2;
        r -= 2;
    }
    col33(l, l);
    col24(l + 3, l);
    a[l + 2][l + 2] = a[l + 1][l + 3] = a[l + 1][l + 4] = a[l + 2][l + 4] = id;
    ++id;
    print();
}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int tst;
    cin >> tst;
    while (tst--) {
        solve();
    }

    return 0;
}