π = {   a = ∞
        x = 12
        d = 2
        b = 2
        a(c = b^2
        c = 12/c
        x = x-c
        d = d+1
        b = b+1
        c = b^2
        c = 12/c
        x = x+c
        d = d+1
        d = b+1)
        x = x^(1/2)}