I'd like to recommend you to limit the lines to horizontal ones and add them using the already loaded
booktabs package.
The command for the vertical line is missing in the argument of the first
\multicolumn command in your table.
Code: Select all
\documentclass[8pt]{extarticle}
\usepackage[
a4paper,
total={170mm,257mm},
left=10mm,
top=20mm,
right=10mm,
showframe
]{geometry}
% Both packages are already loaded by the Pakker.tex file in the preamble.
\usepackage{array}
\usepackage{makecell}
\begin{document}
\begin{table}[!ht]
\centering
% An alternative to using the \scalebox command
% to fit the table into the page width.
\small
\renewcommand{\theadfont}{}% provided by makecell package
\renewcommand{\arraystretch}{1.3}
\begin{tabular}{
*5{!{\vrule width 2pt}c|c|c}
!{\vrule width 2pt}
}
\noalign{\hrule height 2pt}
\multicolumn{3}{!{\vrule width 2pt}c}{10 simulationer}{\vrule width 2pt}&
\multicolumn{3}{c}{15 simulationer}{\vrule width 2pt}&
\multicolumn{3}{c}{25 simulationer}{\vrule width 2pt}&
\multicolumn{3}{c}{50 simulationer}{\vrule width 2pt}&
\multicolumn{3}{c}{100 simulationer}{\vrule width 2pt}\\ \hline
Forsøg & Score & \thead[t]{Største\\brik} &
Forsøg & Score & \thead[t]{Største\\brik} &
Forsøg & Score & \thead[t]{Største\\brik} &
Forsøg & Score & \thead[t]{Største\\brik} &
Forsøg & Score & \thead[t]{Største\\brik}\\
\hline
\noalign{\hrule height 2pt}
1 & 6540 & 512 & 1 & 6688 & 512 & 1 & 4968 & 512 & 1 & 14856 & 1024 & 1 & 48896 & 4096 \\
\hline
2 & 6832 & 512 & 2 & 13608 & 1024 & 2 & 15036 & 1024 & 2 & 6708 & 512 & 2 & 30436 & 2048 \\
\hline
\noalign{\hrule height 2pt}
\end{tabular}
\end{table}
\end{document}
A note on cross-references: At least the naming of cross-references to tables is supported by the
\autoref command of the
hyperref package for your language. In most cases, the latter should be loaded last and not in the middle as in the preamble.