# Array with nested slashes and parenthesis

I am trying to TeX the following schematic:

using some fiddling around with multirows. However, everything's messed up, so I suppose there must be a more elegant way. How? So far, my attempts using blkarray also do not work out quite well…

Here is a proposal using a combination of array and matrix. I've reduced the vertical space between lines using, for example, [-1.3em]. Also reduced the space between the contents and large outside brackets using \mkern-8mu, for example. You can change these numbers as you see fit. Adjustments to the column separation can be made using \arraycolsep.

\documentclass[12pt,a4paper]{article}
\usepackage{mathtools}

\begin{document}

$\arraycolsep=3pt \left(\mkern-8mu \begin{array}{cccc} & & & \begin{matrix} a\\b \end{matrix} \\[-1.3em] & & \left( \begin{matrix} e\\f \end{matrix} \middle/ \begin{matrix} c\\d \end{matrix} \right) & \\[-1em] & g & & \\[-1.3em] \left( \begin{matrix} j\\k \end{matrix} \middle/ \begin{matrix} h\\i \end{matrix} \right) & & & \end{array} \mkern-3mu\right)$

\end{document}

• This is really cool! I think it is even a bit handier if one puts the lonesome $g$ into a dummy matrix. Did you get the 1.3em just by trying, or is there a deeper reason? Jul 25, 2018 at 10:51
• No deep reason. I started off by putting [-1em] after each line break. And just adjusted them from there.
– Milo
Jul 25, 2018 at 11:07
• By the way, I'm curious, what does the word solidusses mean??
– Milo
Jul 25, 2018 at 11:09
• Unicode uses the name solidus it to refer to a slash. Since I am unaware of Latin, I do not know the proper plural form. ~~Solidūs?~~ Solidi, according to Wikipedia Jul 25, 2018 at 12:33