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

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

Find N.

(In reply to Answer only by Ady TZIDON)

I think you forgot the case when both sets have 6 elements, then there is no where to place 6 as this would violate either rule 3 or 4.

Posted by Daniel on 2015-04-13 13:47:57