I'm not really sure what you're asking, but if you want to calculate the first two terms of the sequence after a1, then here's the answer:
If a1=2, then a2 = -3(a1 - 1)^2 = -3(2-1)^2 = -3*(-1)^2 = -3*1 = -3.
Then, a3 = -3(a2 - 1)^2 = -3(-3-1)^2 = -3(-4)^2 = -3*16 = -48.
I'm sorry if this is not what you wanted.
