\documentclass[12pt,a4paper]{article}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsthm}
\usepackage{enumitem}
\usepackage{graphicx}
\usepackage[left=2.5cm,right=2.5cm,top=2.5cm,bottom=2.5cm]{geometry}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\draw (6,0) -- (6,-24);
\draw (6,-24) -- (12,-24);
\draw (12,-24) -- (12,0);
\draw (6,0) -- (12,0);
\draw (0,-6) -- (18,-6);
\draw (18,-6) -- (18,-12);
\draw (18,-12) -- (0,-12);
\draw (0,-6) -- (0,-12);
\draw (6,-18) -- (12,-18);
\draw (8,0) -- (8,-24);
\draw (10,0) -- (10,-24);
\draw (0,-8) -- (18,-8);
\draw (0,-10) -- (18,-10);
\draw (6,-2) -- (12,-2);
\draw (6,-4) -- (12,-4);
\draw (6,-14) -- (12,-14);
\draw (6,-16) -- (12,-16);
\draw (6,-18) -- (12,-18);
\draw (6,-20) -- (12,-20);
\draw (6,-22) -- (12,-22);
\draw (2,-6) -- (2,-12);
\draw (4,-6) -- (4,-12);
\draw (14,-6) -- (14,-12);
\draw (16,-6) -- (16,-12);
\end{tikzpicture}
\end{document}
I am trying to enter in each of the squares of this picture a number such that for each of the 6 "obvious" big squares, the entries are 0,1,2,3,4,5,6,7,8.
I thought maybe using a for loop, but I need to know how to enter the number in the center of the small squares.
Kind Regards.




