diff --git a/macros.tex b/macros.tex
index 0cb4c84..8fd341d 100644
--- a/macros.tex
+++ b/macros.tex
@@ -34,6 +34,7 @@
 %% Usual sets
 \newcommand{\RR}{\xspace\ensuremath{\mathbb{R}}\xspace}
 \newcommand{\ZZ}{\xspace\ensuremath{\mathbb{Z}}\xspace}
+\newcommand{\NN}{\xspace\ensuremath{\mathbb{N}}\xspace}
 \newcommand{\CC}{\xspace\ensuremath{\mathbb{C}}\xspace}
 \newcommand{\QQ}{\xspace\ensuremath{\mathbb{Q}}\xspace}
 \newcommand{\Zq}{\xspace\ensuremath{\mathbb{Z}_q}\xspace}