diff --git a/preamble.sty b/preamble.sty
index 15532fe..4188548 100644
--- a/preamble.sty
+++ b/preamble.sty
@@ -37,6 +37,7 @@
 \newcommand{\parens}[1]{\left(#1\right)}
 \newcommand{\bracs}[1]{\left\{#1\right\}}
 \newcommand{\braks}[1]{\left[#1\right]}
+\newcommand{\braksn}[1]{[#1]}
 \newcommand{\angles}[1]{\left\langle#1\right\rangle}
 \newcommand{\abs}[1]{\left|#1\right|}
 \newcommand{\bracsn}[1]{\{{#1}\}}