Do you mean the patchy black and white or black with white chest and paws?
Patchy black and white is called Harlequin and they are very expensive - can cost £3K a pup!
Black with white chest and paws is Boston Black or Mantle.
Remember Danes are very soppy and loyal and love their humans - they are not a dog to be left alone for long periods or your new house will be a good example of a demolition exhibition :D They eat - a lot. They do need regular exercise and careful raising as puppies. Only buy from a reputable breeder who hipscores.
You could have a look at
Ravendane for further info on pups.