Quote from: onemanatatime on April 28, 2017, 05:11:42 AM

How often does XPM find a new prime number? Does it get longer to find each new prime number?

A new prime chain is found with each block (~1minute). Within a prime chain, each number is prime and is larger than the one before. Currently we're looking for chains with at least 10 consecutive primes. The first prime in the chain is guaranteed to be at least 256bits long - but could actually be much much bigger depending on the primorial and multiplier chosen. Miners don't tend to look for larger primes as the maths involved takes longer - hence mining is slower.

This is a very intellectually challenging coin to write a good miner for - there are several conflicting aspects that directly influence mining speed and pretty much every design decision becomes a trade off

For example:
1. Mining with a large primorial increases the base prime probability at the cost of fundamentally larger numbers that are slower to verify and work with.
2. Mining with lots of primes increases the sieve accuracy and reduces the number of false positives that then get passed through to chain length determination, but using too many primes above a certain threshold removes so few candidates that its actually faster to deal with false positives!