Would you consider adding a stride option that works in address and vanity mode?
Well It is not so simple, i already try it before but my first code was wrong
My use case - I've found a good amount of 13zb1hQbWV prefix matches for puzzle 66 so far. When I convert their hex key into their base10 decimal number, I notice many of them (about 1/3) have a factor of 13 and/or 17. An example is 3FEE2509944801483 (13zb1hQbWVECopz4XMEYH8e2t2gX4v4Us3) = (decimal) 73706563070708421763 = 7 × 13 × 809962231546246393.
Nice finding, from a statistical point of view, is your data set Significant?
In the 66 bit space maybe there around of 12344 address that start with 13zb1hQbWV, so I don't know how many we require so demonstrate that those prime factors are relevant or not.
Another thing is that there is no relationship between the prime factors of a private key and the generated address prefix, I can found a lot of address that aren't related to 13zb1hQbWV so the number of "(about 1/3)" is just some statistical
According to some research that i just did the percentage of numbers that has 11 or 13 as factor is near to 20%, that may vary from one rank to another
I bet that half of your data set has 2 as prime factor and other 1/3 has 3 as prime factor no?
I really may consider to add the stride option if you share your data set with me in public or in private.