R = w2*w3 S = R^2 t0 = 1+w2 t1 = t0+w3 t2 = R*t1 T = t2+S t3 = d2overd1plus1*S t4 = d1+T t5 = t4+t3 t6 = 1/t5 t7 = T*t6 w5 = t7+w1