diff --git a/Alea/Random.hs b/Alea/Random.hs
index 4902c83..f173e12 100644
--- a/Alea/Random.hs
+++ b/Alea/Random.hs
@@ -15,4 +15,4 @@ randPick ys n gen = (x : xs', gen'')
 
 -- Generate k random number in the range [0, n)
 randWords :: Int -> Int -> IO [Int]
-randWords n k = getStdRandom (randPick [0..n] k)
+randWords n k = getStdRandom (randPick [0..n-1] k)