pom y = all (/=0) (map (mod y) [2..y-1])
funkcja x= filter pom [2..x-1]

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splaszcz x = foldl (\list el -> list ++ el) [] x

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funkcjaa i=map(length i* )i

funkcja a = map (\ x -> x* length(a)) a

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mean :: (Fractional a, Foldable t) => t a -> a
mean xs =(sum xs)/ (fromIntegral(length xs))
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mean :: (Fractional a, Foldable t) => t a -> a
mean xs =(foldr (+) 0 xs)/ (fromIntegral(length xs))