N is the number of ordered pairs of non-empty sets P and Q that have the following properties:

- P
**⋃** Q ={1,2,3,4,5,6,7,8,9,10,11,12}, and:
- P
**⋂** Q = Φ, and:
- The number of elements of P is not an element of P, and:
- The number of elements of Q is not an element of Q

Find N.

(In reply to

re: Answer only by Daniel)

You are right.

I've solved it too fast, trying a 5-element set, and justifying the

** 2^(n-2) answer.**

**Please see my edited version.**