How many bees for three frame medium mating nucs?

[BeeCurious]

I'm starting to put medium frames of brood above queen excluders to use in my queen castles when my virgin queens arrive.

I'm concerned about over stocking / under stocking the mating nucs with bees.

My intention is to have mostly sealed brood with just a small amount of older larvae, a frame of honey and pollen, and a mostly empty frame possibly containing some nectar.

With that makeup, would the bees covering the prepared frames be adequate? I picture there being about two cups of bees...

How many nurse bees should a three frame medium mating nuc be stocked with?

[gmcharlie]

MAteing nucs need about 2 cups worth of bees, more is fine but not needed. Less and she won't show a good pattern of laying as theree are no nurse bees to feed the larve.