diff --git a/doc/tutorial.rst b/doc/tutorial.rst
index b7197b664356e1dcde3fc8c107b86806302e12f1..dbe7aae3fcd7623c5399c47ba0e1eafcd0ebfd5c 100644
--- a/doc/tutorial.rst
+++ b/doc/tutorial.rst
@@ -560,7 +560,7 @@ Consider this example:
     #define lid(N) ((int) get_local_id(N))
     ...
       for (int i_outer = 0; i_outer <= -1 + (15 + n) / 16; ++i_outer)
-        for (int i_inner = 0; i_inner <= (-16 + n + -16 * i_outer >= 0 ? 15 : -1 + n + -16 * i_outer); ++i_inner)
+        for (int i_inner = 0; i_inner <= (-17 + n + -16 * i_outer >= 0 ? 15 : -1 + n + -16 * i_outer); ++i_inner)
           a[16 * i_outer + i_inner] = 0.0f;
     ...