All we need are these facts: i2 = -1 (-1)ODD = -1, (-1)EVEN = 1 -i6699 = -(i6699) = -(i6698+1) = -(i6698i1) = -(i2·3349i1) = -(i2)3349i = -(-1)3349i = -(-1)i = i Edwin