Then between the 429th - 463rd prime numbers, it uses the whole prime numbers (they have 8 digits in this interval) concatenated.
Starting at F, 0 and 2 means ascend a scale step, 1 means descend a scale step.
When it's done, it hooks up at the prime number where the 1st part is at the monent and uses the same algorithm as the 2nd part had at the beginning of the piece.
When the 2nd part is done, the pitch jumps back to the default F, and then continues as before to the end.