sweater update

Two inches into the sweater and I am on a set up row, which I have knitted and ripped six times.  I took it out and counted every stitch.  I need to find the center back stitch so that I can set the pattern properly.  Ok.
270/2=135+1= center stitch right? and 270/35=7.7  That means that 7X35 = 245.  270-245=25.  25/2=12.5
So if I am not entirely messed up I will have 12 stitches on one side and 13 stitches on the other side of the front for a border before I begin the pattern for the body.  That means that I can find a nice 12 stitch border pattern to go up the front sides and everybody is happy and the back is centered right?  Right?

Shut up.  I'm counting
I need a 12 stitch spider.