diff --git a/tests/Number.hs b/tests/Number.hs
index aaaba86..f63a840 100644
--- a/tests/Number.hs
+++ b/tests/Number.hs
@@ -20,22 +20,21 @@ serializationVectors =
     ]
 
 tests = testGroup "number"
-    [ testProperty "num-bits" $ \(Int0_2901 i) ->
-        if i == 0 then True else
-            and [ (numBits (2^i-1) == i)
-                , (numBits (2^i) == i+1)
-                , (numBits (2^i + (2^i-1)) == i+1)
-                ]
+    [ testProperty "num-bits" $ \(Int1_2901 i) ->
+        and [ (numBits (2^i-1) == i)
+            , (numBits (2^i) == i+1)
+            , (numBits (2^i + (2^i-1)) == i+1)
+            ]
     , testProperty "num-bits2" $ \(Positive i) ->
         not (i `testBit` numBits i) && (i `testBit` (numBits i - 1))
-    , testProperty "generate-param" $ \testDRG (Int0_2901 bits)  ->
+    , testProperty "generate-param" $ \testDRG (Int1_2901 bits)  ->
         let r = withTestDRG testDRG $ generateParams bits (Just SetHighest) False
          in r >= 0 && numBits r == bits && testBit r (bits-1)
     , testProperty "generate-param2" $ \testDRG (Int0_2901 m1bits) ->
         let bits = m1bits + 1 -- make sure minimum is 2
             r = withTestDRG testDRG $ generateParams bits (Just SetTwoHighest) False
          in r >= 0 && numBits r == bits && testBit r (bits-1) && testBit r (bits-2)
-    , testProperty "generate-param-odd" $ \testDRG (Int0_2901 bits) ->
+    , testProperty "generate-param-odd" $ \testDRG (Int1_2901 bits) ->
         let r = withTestDRG testDRG $ generateParams bits Nothing True
          in r >= 0 && odd r
     , testProperty "generate-range" $ \testDRG (Positive range) ->
diff --git a/tests/Utils.hs b/tests/Utils.hs
index bd0f829..11622c4 100644
--- a/tests/Utils.hs
+++ b/tests/Utils.hs
@@ -46,9 +46,15 @@ instance Arbitrary ArbitraryBS0_2901 where
 newtype Int0_2901 = Int0_2901 Int
     deriving (Show,Eq,Ord)
 
+newtype Int1_2901 = Int1_2901 Int
+    deriving (Show,Eq,Ord)
+
 instance Arbitrary Int0_2901 where
     arbitrary = Int0_2901 `fmap` choose (0,2901)
 
+instance Arbitrary Int1_2901 where
+    arbitrary = Int1_2901 `fmap` choose (1,2901)
+
 -- | a integer wrapper with a better range property
 newtype QAInteger = QAInteger { getQAInteger :: Integer }
     deriving (Show,Eq)