knitting: a break to compute

I have just done some math and worked out that a large square on this afghan consists of 4705 stitches. (I did do the math right, didn't I? Cast on 96, knit back, and then decrease two on every alternate row until there are two stitches left, which you knit together. So 2x96 + 2x94 + 2x 92 ... + 2x2 + 1. Right? Which is 192+188+184+180 etc., down by fours until you get to, well, four, and then one more stitch. Right.)

Small square, I get 1201. Rectangle has 2400. I'm not sure why the large square, which is four times the size of a small square, doesn't have four times as many stitches, but it's late and maybe I forgot to add something somewhere -- anyway, though, point is, it's a lot of stitches here. Yoiks.