nextInSeries :: [Integer] -> Integer
nextInSeries = read
             . concatMap (show . length &&& pure . head >>> uncurry (++))
             . group . show . last
nextInSeries :: [Integer] -> Integer
nextInSeries = read
             . concatMap (show . length &&& pure . head >>> uncurry (++))
             . group . show . last
nextInSeries = read
             . concatMap (show . length &&& pure . head >>> uncurry (++))
             . group . show . last