#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll myRand(ll B) {
    return (ull)rng() % B;
}
inline double time() {
    return static_cast<long double>(chrono::duration_cast<chrono::nanoseconds>(chrono::steady_clock::now().time_since_epoch()).count()) * 1e-9;
}

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int q; cin >> q;
    while (q--) {
        int n; cin >> n;
        vector<vector<char>> v(n, vector<char>(n, '.'));
        if (n%6 == 1) {
            for (int i = 0; i < n; i += 2) {
                for (int j = 0; j+1 < n; j += 3) {
                    v[i][j] = v[i][j+1] = '#';
                }
            }
            for (int i = 0; i+1 < n; i += 3) {
                v[i][n-1] = v[i+1][n-1] = '#';
            }
        }
        else if (n%6 == 2) {
            for (int i = 0; i+3 < n; i += 2) {
                for (int j = 0; j+1 < n; j += 3) {
                    v[i][j] = v[i][j+1] = '#';
                }
            }
            for (int i = 0; i < n; i += 2) {
                v[n-2][i] = v[n-1][i] = '#';
            }
        }
        else if (n%6 == 3) {
            for (int i = 0; i < n; i += 2) {
                for (int j = 0; j+3 < n; j += 3) {
                    v[i][j] = v[i][j+1] = '#';
                }
            }
            for (int i = 0; i+1 < n; i += 3) {
                v[i][n-3] = v[i+1][n-3] = '#';
                v[i][n-1] = v[i+1][n-1] = '#';
            }
        }
        else if (n%6 == 4) {
            for (int i = 0; i < n; i += 2) {
                for (int j = 0; j+4 < n; j += 3) {
                    v[i][j] = v[i][j+1] = '#';
                }
            }
            for (int i = 0; i+4 < n; i += 3) {
                v[i][n-3] = v[i+1][n-3] = '#';
                v[i][n-1] = v[i+1][n-1] = '#';
            }
            v[n-4][n-4] = v[n-4][n-3] = '#';
            v[n-4][n-1] = v[n-3][n-1] = '#';
            v[n-1][n-1] = v[n-1][n-2] = '#';
            v[n-1][n-4] = v[n-2][n-4] = '#';
        }
        else if (n%6 == 5) {
            for (int i = 0; i < n; i += 2) {
                for (int j = 0; j+1 < n; j += 3) {
                    v[i][j] = v[i][j+1] = '#';
                }
            }
        }
        else {
            for (int i = 0; i < n; i += 2) {
                for (int j = 0; j+6 < n; j += 3) {
                    v[i][j] = v[i][j+1] = '#';
                }
            }
            for (int i = 0; i+6 < n; i += 3) {
                v[i][n-6] = v[i+1][n-6] = '#';
                v[i][n-4] = v[i+1][n-4] = '#';
                v[i][n-2] = v[i+1][n-2] = '#';
            }
            v[n-6][n-6] = v[n-5][n-6] = '#';
            v[n-6][n-4] = v[n-5][n-4] = '#';
            v[n-6][n-2] = v[n-6][n-1] = '#';
            v[n-4][n-2] = v[n-4][n-1] = '#';
            v[n-3][n-6] = v[n-3][n-5] = '#';
            v[n-1][n-6] = v[n-1][n-5] = '#';
            v[n-1][n-3] = v[n-2][n-3] = '#';
            v[n-1][n-1] = v[n-2][n-1] = '#';
        }

        for (int i = 0; i < n; ++i) {
            for (int j = 0; j < n; ++j) {
                cout << v[i][j];
            }
            cout << '\n';
        }
    }
}