diff --git a/15.py b/15.py
index 399955c..0b424af 100755
--- a/15.py
+++ b/15.py
@@ -1,13 +1,15 @@
-import sys;
-
-def factorial(num):
-    result = 1;
-    for x in range (num,1,-1):
-        result *= x;
-    return result;
-
-def binomial(m,n):
-    return factorial(m)/(factorial(n)*factorial(m-n));
-
-dimension = int(sys.argv[1]);
-print "Result is: " + str(binomial(dimension*2,dimension));
+#!/usr/bin/python
+
+import sys;
+
+def factorial(num):
+    result = 1;
+    for x in range (num,1,-1):
+        result *= x;
+    return result;
+
+def binomial(m,n):
+    return factorial(m)/(factorial(n)*factorial(m-n));
+
+dimension = int(sys.argv[1]);
+print "Result is: " + str(binomial(dimension*2,dimension));
diff --git a/16.py b/16.py
index 2dbbe74..efb196e 100755
--- a/16.py
+++ b/16.py
@@ -1,12 +1,14 @@
-import math;
-import sys;
-
-def sumDigits(num):
-    sum = 0;
-    for i in range (0,len(num)):
-        sum += int(num[i]);
-
-    return sum;
-
-
-print "Result is: " + str(sumDigits(str(int(math.pow(int(sys.argv[1]),int(sys.argv[2]))))))
+#!/usr/bin/python
+
+import math;
+import sys;
+
+def sumDigits(num):
+    sum = 0;
+    for i in range (0,len(num)):
+        sum += int(num[i]);
+
+    return sum;
+
+
+print "Result is: " + str(sumDigits(str(int(math.pow(int(sys.argv[1]),int(sys.argv[2]))))))
diff --git a/17.py b/17.py
index c23dd48..f5a301d 100755
--- a/17.py
+++ b/17.py
@@ -1,3 +1,5 @@
+#!/usr/bin/python
+
 import sys;
 
 def getLetterNum(num):