diff --git a/e_11.py b/e_16.py
similarity index 77%
rename from e_11.py
rename to e_16.py
index cd166df..f79a16a 100755
--- a/e_11.py
+++ b/e_16.py
@@ -4,7 +4,7 @@
  # jlengrand
  #Created on : Fri Jan 13 15:24:59 CET 2012
  #
- # DESCRIPTION : Solves problem 11 of Project Euler
+ # DESCRIPTION : Solves problem 16 of Project Euler
  2^15 = 32768 and the sum of its digits is 3 + 2 + 7 + 6 + 8 = 26.
  What is the sum of the digits of the number 2^1000?
  ##---
@@ -13,8 +13,7 @@ def sum_power_2(value):
     """
     Returns the sum of the digits of 2^value
     """
-    
-    return 1
+    return sum([int(el) for el in list(str(pow(2, value)))])
 
 if __name__ == '__main__':
     print "Answer : %d" % (sum_power_2(1000))
diff --git a/e_20.py b/e_20.py
new file mode 100755
index 0000000..a158f04
--- /dev/null
+++ b/e_20.py
@@ -0,0 +1,22 @@
+#!/usr/bin/env python 
+"""
+ ##---
+ # jlengrand
+ #Created on : Fri Jan 13 15:41:12 CET 2012
+ #
+ # DESCRIPTION : Solves problem 20 of Project Euler
+ n! means n  (n  1)  ...  3  2  1
+ For example, 10! = 10  9  ...  3  2  1 = 3628800,
+ and the sum of the digits in the number 10! is 3 + 6 + 2 + 8 + 8 + 0 + 0 = 27.
+ Find the sum of the digits in the number 100! 
+ ##---
+"""
+def sum_fact(value):
+    """
+    Returns the sum of digits in value!
+    """
+    
+    return 1
+
+if __name__ == '__main__':
+    print "Answer : %d" % (sum_fact)