sigma,tau,x0,x1

sigma2 = sigma^40491355905
g0 = sigma2^2
u0 = (x0*tau)^40491355905
u1 = (x1*tau)^40491355905
d0 = u0*x0^-1
z0 = x0^sigma2
c0 = d0^-1*z0^-1*d0*z0
dg = d0^g0
hc = dg^-1*d0^-1*dg*d0
h0 = x0^g0*x0*dg*d0*d0^2*hc

h0*u1^-1*x1^sigma*c0