Where do random numbers come from really?
Uniformly distributed random variates Xi = remainder(aXi-1 / m)
For example, a= 75 m= 231 -1
Given two Xj Xk such uniform random variates,
Normally distributed random variates can be made
Xi = sqrt(-2log(Xj)) cos(2pXk) (NR, Press et al. p. 279-89)