diff --git a/aern2-real.cabal b/aern2-real.cabal
--- a/aern2-real.cabal
+++ b/aern2-real.cabal
@@ -4,10 +4,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: a941e85f57a40b5cf3c43916267832d6e3d3d06355ebdf3245776b4d564ec0cf
+-- hash: c67f4a27fe078f22681a08242d1e8a0ed286ea4b52c96a755e45c8ce04d402c7
 
 name:           aern2-real
-version:        0.2.5.0
+version:        0.2.6.0
 synopsis:       Real numbers as sequences of MPBalls
 description:    Please see the README on GitHub at <https://github.com/michalkonecny/aern2/#readme>
 category:       Math
@@ -61,12 +61,12 @@
   ghc-options: -Wall
   build-depends:
       QuickCheck
-    , aern2-mp >=0.2.5
+    , aern2-mp >=0.2.6
     , base ==4.*
     , collect-errors >=0.1.5
     , hspec
     , integer-logarithms
-    , mixed-types-num >=0.5.5
+    , mixed-types-num >=0.5.7
   default-language: Haskell2010
 
 test-suite aern2-real-test
@@ -93,11 +93,11 @@
   ghc-options: -threaded -rtsopts -with-rtsopts=-N -Wall
   build-depends:
       QuickCheck
-    , aern2-mp >=0.2.5
+    , aern2-mp >=0.2.6
     , aern2-real
     , base ==4.*
     , collect-errors >=0.1.5
     , hspec
     , integer-logarithms
-    , mixed-types-num >=0.5.5
+    , mixed-types-num >=0.5.7
   default-language: Haskell2010
diff --git a/src/AERN2/Real/Field.hs b/src/AERN2/Real/Field.hs
--- a/src/AERN2/Real/Field.hs
+++ b/src/AERN2/Real/Field.hs
@@ -70,24 +70,28 @@
 
 instance
   (CanPow b e, HasOrderCertainly b Integer, HasOrderCertainly e Integer,
-   HasEqCertainly b Integer, CanTestInteger e) 
+   HasEqCertainly b Integer, CanTestInteger e, CanTestIsIntegerType b, CanTestIsIntegerType e)
   =>
   CanPow (CSequence b) (CSequence e) 
   where
   type PowType (CSequence b) (CSequence e) = CSequence (PowType b e)
   pow = lift2 pow
+  type PPowType (CSequence b) (CSequence e) = CSequence (PPowType b e)
+  ppow = lift2 ppow
 
 $(declForTypes
   [[t| Integer |], [t| Int |], [t| Rational |]]
   (\ e -> [d|
 
   instance 
-    (CanPow b $e, HasOrderCertainly b Integer, HasEqCertainly b Integer)
+    (CanPow b $e, HasOrderCertainly b Integer, HasEqCertainly b Integer, CanTestIsIntegerType b)
     =>
     CanPow (CSequence b) $e 
     where
     type PowType (CSequence b) $e = CSequence (PowType b $e)
     pow = lift1T pow
+    type PPowType (CSequence b) $e = CSequence (PPowType b $e)
+    ppow = lift1T ppow
 
   |]))
 
@@ -96,12 +100,14 @@
   (\ b -> [d|
 
   instance 
-    (CanPow $b e, HasOrderCertainly e Integer, CanTestInteger e)
+    (CanPow $b e, HasOrderCertainly e Integer, CanTestIsIntegerType e, CanTestInteger e)
     =>
     CanPow $b (CSequence e) 
     where
     type PowType $b (CSequence e) = CSequence (PowType $b e)
     pow = liftT1 pow
+    type PPowType $b (CSequence e) = CSequence (PPowType $b e)
+    ppow = liftT1 ppow
   |]))
 
 ---------------------------------------------------
diff --git a/src/AERN2/Real/Type.hs b/src/AERN2/Real/Type.hs
--- a/src/AERN2/Real/Type.hs
+++ b/src/AERN2/Real/Type.hs
@@ -42,6 +42,9 @@
     where
     p = cseqPrecisions !! cseqShowDefaultIndex
 
+instance (CanTestIsIntegerType t) => CanTestIsIntegerType (CSequence t) where
+  isIntegerType (CSequence s) = isIntegerType (head s)
+
 cseqShowDefaultIndex :: Integer
 cseqShowDefaultIndex = 7