diff --git a/amicable.sage b/amicable.sage
old mode 100644
new mode 100755
index 050b616..6bb6c57
--- a/amicable.sage
+++ b/amicable.sage
@@ -1,4 +1,6 @@
+#!/usr/bin/env sage
 # -*- coding: utf-8 -*-
+
 import sys
 from multiprocessing import Pool, cpu_count
 from traceback import print_exc