Wiring subs

I am going to hook up three dual 4 ohm voice coil subs to a mono block 1ohm stable amp.  And what I was wonder is if you wire the first two subs in series than the third in parallel than wire all three together in parallel dont this equal 1.3ohm because 8 and 8 is 4 and 4 and 2 is 1.3 if so I was wonder if it is ok to run the subs this way and if not why.  Hopefully some one with more knowledge than me on this can help because if not Im just going to run them all in series than parallel to get 2.6 ohm.  Any advice will help.

     If you hook up all the in series you will reach 2.7  You would need 3   2ohm woofers.