Update README.md

Author: Zheyuan Chen

README.md

@@ -100,7 +100,7 @@ print(1 /to/ INF /take/ 5)
 # return [1, 2, 3, 4, 5]
 
 # print all combinations of [1..3] * [4..6]
-print([(x, y) for x, y in (1 /to/ 3) * (4 /to /6)])
+print([(x, y) for x, y in (1 /to/ 3) * (4 /to/ 6)])
 # return [(1, 4), (1, 5), (1, 6), (2, 4), (2, 5), (2, 6), (3, 4), (3, 5), (3, 6)]
 ```