What sheep do you need to mate in order to try and get the rare pink sheep?

What types of sheep must you mate in order to have a chance in getting the pink sheep? What is the percent of getting it? I looked in the breeding section of the wiki and it said that you could technically get the pink sheep without the use of dyes.

Sheep colour traits are passed on by their parents, meaning you will probably need to find a pink sheep in order to breed a pink sheep, which is counter-intuitive. A chance of spawning a pink sheep using the Sheep Egg is 0.164%

Luckily, there's an easier way. You can dye sheep different colours, and those colours are passed on to their children when they breed. Sheep dyed a certain colour will even keep that colour after being shorn, and having their wool regenerate!

To dye a Sheep Pink, you first need the items

• Rose Red (from Roses)
• Bonemeal (from Bones)

Two items fairly easy to come by. Combining them in your inventory windows produces 2 Pink Dye.

Use these Pink Dye items on a pair of sheep, and breed them normally. You'll have a small flock of pink sheep in no time!

White and red, of course.

The chance is pretty high. I once accidentally let one white sheep in with a herd of red ones (with an automatic feeder) and before long it was riddled with pink sheep.

Alternatively, just use pink dye on any sheep.

The reason the wiki says you can get pink sheep without dyes is because they spawn naturally in the world, though very rarely. It doesn't mean there's some secret breeding trick to get one.

Both answers provided by SevenSidedDie and Robotnik are mostly correct, I'm going to address the details here.

A newborn sheep will be colored depending on the colors of the parents. The Wiki explains it quite well:

If the parents have 'compatible' wool colors (meaning that the corresponding dye items could be combined into a third dye color), the resulting lamb will be a mix of their colors (e.g., blue sheep + white sheep = light blue lamb). Otherwise, the lamb will be the same color as one of the parents, chosen at random.

Thus, there are two ways to get a pink sheep: You can mate a red sheep (dye one with a Rose Red dye) and a white sheep (either found naturally, or by dying one white with Bone Meal, as suggested by Robotnik), or you can pre-mix the Rose Red and Bone Meal together on a crafting table to make Pink Dye, and then dye a sheep with that.

Thus, if you know what you're doing, the chance of obtaining a pink sheep is 100%. :-)