Prints lists of numbers which are the sum of two powers of a given base

PowerSum.hs

isPowerSum :: Int -> Int -> Bool
isPowerSum p x= any (==x) [a + b | a <- shortPows, b <- shortPows] where
  shortPows = takeWhile (<x) . map (p^) $ [0..]

powerSequence :: Int -> [Int]
powerSequence p = filter (isPowerSum p) [1..]

sq1 = take 20 . powerSequence $ 2
sq2 = take 20 . powerSequence $ 3
sq3 = take 20 . powerSequence $ 5
sq4 = take 20 . powerSequence $ 7

main :: IO()
main = do 
	print sq1
	print sq2
	print sq3
	print sq4