Not quite sure. I'm sure there is a way you can download it, and it would probably run, but you would need a Tablet that is Multi- USB compatable, saying that it allows the use of a mouse and a keyboard. If thats the case, I'm sure it would work. But, I don't own a tablet, so don't rely on me.
I went to staples one day and put minecraft on the dell imspiron duo they had there. Links the bottom. when i played minecraft, it lagged a lot. my point is that if the said tablet has one of those intel atom processors or teh amd equivalent, avoid it, minecraft will lag a lot. If your laptop has the intel integrated graphics, chances are it will lag. just to to notebook check and look up your gpu and anything in the low midrange and above should handle minecraft at a decent frame rate. anything below and you are asking for lag.
If your going to buy a computer (not a laptop) for Minecraft gaming, I suggest a Mac. Configuring and dragging and dropping and moving things around is much easier on a Mac. They are made to run fast, so they don't run a lot of programs, but the programs that they do run go very fast. I play Minecraft on my Macbook, my Mac, and a Dell PC, and the fastest of the 3 is the Mac, then Macbook, then the PC. Macs take some getting used to but I can program a server in 3 minutes on the Mac as apposed to 30 minutes on my PC, even after doing it many times. I know that's not what this topic was about, but if you are buying a $500 tablet anyways, go ahead and buy the Mac, especially if you are only buying it to play Minecraft.
Theoretically, you can run Minecraft on any platform that supports Java and has enough resources. Of course, controls and all the such are a separate question. I would not dismiss the possibility to run Minecraft on a tablet; as for using it wholly, specific tablets can be connected to external controllers.