About 20 years ago I caught an article about a graduate student who had found an algoritm which would return the n-th digit of [tex] \pi [/tex] without needing to compute the preceding digits. In other words you could ask for the 812th digit of [tex] \pi [/tex] and it would spit it out without computing the prior 811 digits. There was a computer program in the work written in Fortran. The rub is that it only worked in base 16. Is anyone familiar with a special connection between base 16 and an easier way to compute digits of [tex] \pi [/tex]?