title: How do I remove specific vertical lines in a longtable
body: <p>Inmy table below I have six months divided into weeks. I have been trying to have vertical lines only on the 4th, 8th, 12th, 16th, 20th an 24th week, i.e. every month only, or make every 4th vertical line thicker, without any success. Is this possible. Or my searches on stackoverflow have not worked for me. I will appreciate any help.</p>
  
  <pre><code>\documentclass[11pt,twoside,fleqn]{report}
  \usepackage{array,booktabs,tabularx} % also loads 'array' package
  \newcolumntype{C}{&gt;{\centering\arraybackslash}X} % centered version of 'X' columns
  
  \usepackage{ltablex} 
  \usepackage{longtable}
  \usepackage[svgnames,table]{xcolor} % Required to specify font color
  \setlength{\arrayrulewidth}{0.5mm}
  \setlength{\tabcolsep}{3pt}
  \renewcommand{\arraystretch}{1.2}
  
  \begin{document}
  \begin{longtable}[H]{|p{3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} |p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm} | p{0.3cm}|p{0.3cm}|p{0.3cm}|p{0.3cm} | p{0.3cm} | p{0.3cm}|}
  \hline
  \setlength{\tabcolsep}{2pt} % for the horizontal padding
  \renewcommand{\arraystretch}{2}% for the vertical padding
  \textbf{first entires} &amp;\cellcolor{orange} &amp;\cellcolor{orange} &amp;\cellcolor{orange} &amp;\cellcolor{orange} &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp;
  \\[0.10cm]
  \hline
  \textbf{second entries} &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; \cellcolor{blue}&amp;\cellcolor{blue} &amp;\cellcolor{blue} &amp;\cellcolor{blue} &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; 
  \\[0.10cm]
  \hline
  \textbf{third entries} &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp;&amp; &amp; &amp; &amp; \cellcolor{orange}&amp; \cellcolor{orange} &amp; \cellcolor{orange} &amp; \cellcolor{orange} &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; 
  \\[0.10cm]
  \hline
  \textbf{End} &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp; &amp;\cellcolor{teal} &amp;\cellcolor{teal} 
  \\[0.10cm]
  \hline
  \bottomrule
  \end{longtable}
  \end{document}
  </code></pre>