Quote:
Originally Posted by ATH
How does this work when the test is designed for P+1 to be smooth?

That's just the way the math works out.
A simple intro:
https://en.wikipedia.org/wiki/Willia...2B_1_algorithm
The thing that needs to be smooth is p(Dp). If (Dp) is 1, then p+1. If (Dp) is 1, then p1.
Note: using P+1 to find P1 factors is inefficient because a) P+1 is slower, and b) you only have a 50% chance of success, where as pure P1 has 100% chance of success. Therefore, if you've already run P1, then P+1 with same bounds is not going to find any additional "p1" factors.