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diff --git a/AufgabeFFP2.hs b/AufgabeFFP2.hs
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+module AufgabeFFP2
+where
+
+-- 1
+
+primes :: [Integer]
+primes = sieve [2 ..]
+
+-- sieve of eratosthenes (according to lecture slides)
+sieve :: [Integer] -> [Integer]
+sieve (x:xs) = x : sieve [ y | y <- xs, mod y x > 0]
+
+-- generate all pairs with map and then filter only the valid ones
+-- TODO: filtering should be optimized, still a bit slow
+pps :: [(Integer, Integer)]
+pps = filter validPair $ map (\x -> (x,x+2)) primes
+        where
+                -- pair is valid if the second component n is a prime
+                -- since simply checking if the Integer is element of the prime-list 
+                -- does not terminate for non-primes, we take the first n primes
+                validPair :: (Integer,Integer) -> Bool
+                validPair (_,maybePrime) = elem maybePrime $ take (fromInteger maybePrime) primes
+                                
+-------------------------------------------------------------------------------
+
+-- 2
+
+-- generates powers of 2        
+pof2s :: [Integer]
+pof2s = [1] ++ (map (2*) pof2s)
+        
+pow :: Int -> Integer
+pow 0 = 1
+pow n = pow (n-1) + pow (n-1)
+
+-- uses memtable for power-calculation
+powFast :: Int -> Integer
+powFast 0 = 1
+powFast n = pof2s !! (n-1) + pof2s !! (n-1)
+
+-------------------------------------------------------------------------------
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