The number of filter surveys                    
This section will demonstrate how to count the number of filtering forms you will be having on  form, that is, we intend to show the real power of the usage of filtering objects and OOF. The aim is to show that playing on the form, you may have many reviews without the user being aware of it. But what are our filtering objects? If we neglect the internal object conditions, filtering object presents a simple switch with two states:
            1)       the state of disconnection – the state mark 0
            2)       the state of connection – the state mark 1
We shall give the label
            n- to the number of primary objects and
            Nv – for the total number of potential reviews
We could utilize the knowledge of our connection technique (binary numbers) and design the form with three objects:    

The total number of reviews is : Nv = 2 ^ n
In order to this number of reviews, we need to have the eliminating filter type (AND operator).
The table presents some of the values for the expression 2^n