How to count layers is a matter of considerable dispute. 

 o Some people count layers of units. But of these people, some count the
   input layer and some don't. 

 o Some people count layers of weights. But I have no idea how they count
   skip-layer connections. 

To avoid ambiguity, you should speak of a 2-hidden-layer network, not a
4-layer network (as some would call it) or 3-layer network (as others would
call it). And if the connections follow any pattern other than fully
connecting each layer to the next and to no others, you should carefully
specify the connections. 

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