Checking if a number is even in Haskell

Even.hs

import Data.Semigroup

data Permutation = Permutation [Int] deriving (Eq, Show)

permute :: Permutation -> [a] -> [a]
permute (Permutation p) xs = (xs !!) <$> p

instance Semigroup Permutation where
    a <> Permutation b = Permutation $ permute a b
    stimes = stimesMonoid

instance Monoid Permutation where
    mempty = Permutation [0..9]

evening = Permutation [6,9,4,2,0,1,8,5,7,3]
isEven x = head $ permute (stimes (5 * x) evening) $ True:False:undefined

main = mapM_ (\x -> putStrLn $ show x ++ " is " ++
        if isEven x then "even" else "odd") [0..30]