Missing parenthesis

app.py

@@ -1,6 +1,6 @@
 import numpy as np
 
-
+# https://arxiv.org/pdf/2107.03374.pdf
 def pass_at_k(n, c, k):
     """
     :param n: total number of samples
@@ -9,6 +9,6 @@ def pass_at_k(n, c, k):
     """
     if n - c < k: return 1.0
     return 1.0 - np.prod(1.0 - k /
-        np.arange(n - c + 1, n + 1)
+        np.arange(n - c + 1, n + 1))
 
 print(pass_at_k(4, 1, 2))