diff --git a/primes.py b/primes.py
index e3cdf36..555a784 100755
--- a/primes.py
+++ b/primes.py
@@ -17,7 +17,7 @@ if max < 1:
 for cnt in range(3, max, 2) :
 	testMax = math.sqrt(cnt)+1
 	isPrime = 1
-	for test in range(3, testMax, 2):
+	for test in range(3, int(testMax), 2):
 		isPrime = cnt % test
 		if isPrime == 0:
 			break