1 files changed, 1 insertions, 3 deletions
diff --git a/montgomery.cls b/montgomery.cls
index 4e56ed4..e285e79 100644
--- a/montgomery.cls
+++ b/montgomery.cls
@@ -10,6 +10,7 @@
 \usepackage{amssymb}
 \usepackage{geometry}
 \usepackage{enumitem}
+\usepackage{amsmath}
 \usepackage{amsthm}
 \usepackage[svgnames]{xcolor}
 \usepackage{thmtools}
@@ -109,9 +110,6 @@
 \setlist[enumerate]{itemsep=0pt,topsep=0pt,label=\alph*)}
 \setlist[enumerate,2]{label=\roman*)}
 
-\DeclareMathOperator{\arity}{arity}
-\DeclareMathOperator{\free}{free}
-
 \AtBeginDocument{
   \setlength{\parskip}{\topsep}
   \setlength{\parindent}{0pt}