diff --git a/CHANGELOG.md b/CHANGELOG.md
index fd1a183..7b8f369 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 1.2.1 - 2016-05-11
+
+The `math.prime_generator` was not working correctly if the parameter `p_min` was an even integer greater than two.
+
 ## 1.2 - 2016-04-27
 
 New packages `dicts` and `dates`. `dates` provides an easy to use timer class to mesure the execution time
diff --git a/README.md b/README.md
index 68a5baa..19139d5 100644
--- a/README.md
+++ b/README.md
@@ -8,8 +8,8 @@ utools
 A set of useful functions to use for various purposes in any Python project.
 
 * Author: Julien CHAUMONT (https://julienc.io)
-* Version: 1.2
-* Date: 2016-04-28
+* Version: 1.2.1
+* Date: 2016-05-11
 * Licence: MIT
 * Url: http://github.com/julienc91/utools
 
diff --git a/docs/conf.py b/docs/conf.py
index 6c134db..0a9f196 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -55,9 +55,9 @@
 # built documents.
 #
 # The short X.Y version.
-version = '1.2'
+version = '1.2.1'
 # The full version, including alpha/beta/rc tags.
-release = '1.2'
+release = '1.2.1'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
diff --git a/setup.py b/setup.py
index b87e2ff..f0212d5 100644
--- a/setup.py
+++ b/setup.py
@@ -4,7 +4,7 @@
 
 setup(
     name="utools",
-    version="1.2",
+    version="1.2.1",
     author="Julien Chaumont",
     author_email="utools@julienc.io",
     description="A set of useful functions to use for various purposes in any Python project",
diff --git a/tests/test_math.py b/tests/test_math.py
index af5245a..a0834df 100644
--- a/tests/test_math.py
+++ b/tests/test_math.py
@@ -133,7 +133,7 @@ def test_prime_generator_with_bad_parameters(p_min, p_max, expected_exception):
 
 # we want to test that the two prime generators functions return the same primes
 @pytest.mark.parametrize("p_min, p_max,", [
-    (2, 4), (4, 2), (3, None), (2, None), (-1, 21)
+    (2, 4), (4, 2), (3, None), (2, None), (-1, 21), (20, 101)
 ])
 def test_prime_generator_and_sieve_of_eratosthenes(p_min, p_max):
     count_max = 1000
diff --git a/utools/__init__.py b/utools/__init__.py
index 28a90a2..7a1faa9 100644
--- a/utools/__init__.py
+++ b/utools/__init__.py
@@ -1,3 +1,3 @@
 # -*- coding: utf-8 -*-
 
-__version__ = "1.2"
+__version__ = "1.2.1"
diff --git a/utools/math.py b/utools/math.py
index 878ead1..43a45f0 100644
--- a/utools/math.py
+++ b/utools/math.py
@@ -106,6 +106,9 @@ def prime_generator(p_min=2, p_max=None):
     q = max(p_min, 3)
     if p_min <= 2 and (p_max is None or p_max >= 2):
         yield 2  # outside the while block to make the double increment optimization work
+    if p_min % 2 == 0:
+        p_min += 1
+
     while p_max is None or q <= p_max:
         if is_prime(q):
             yield q