diff --git a/anki-sin-cos-table.py b/anki-sin-cos-table.py
index bbfc874..fddfb15 100644
--- a/anki-sin-cos-table.py
+++ b/anki-sin-cos-table.py
@@ -1,4 +1,5 @@
 #!/usr/bin/env python3
+from collections import OrderedDict
 from functools import reduce
 
 from sympy import latex, simplify
@@ -14,8 +15,12 @@ def as_csv(*values):
     return reduce(lambda a, b: a + ";" + b, values)
 
 
-xs = map(simplify,
-         [i * pi / 4 for i in range(-16, 16)])
+def deduplicate(iterable):
+    return list(OrderedDict.fromkeys(iterable))
+
+
+xs = sorted(deduplicate(map(simplify,
+                            [i * pi / 4 for i in range(-16, 16)] + [i * pi / 6 for i in range(-24, 24)])))
 
 for x in xs:
     for f in [sin, cos, tan]: