Originally posted by: DrPizza
Anyone else? I'm usually really good at following math textbooks. I can't make rhyme or reason out of his first sieve for double primes. I can't read step 6 either (I can barely make out "mod")
I couldnt' figure it out either until he explained it a bit, I also asked about step 6 too...
My understanding is that he removes all the multiples of 2 and 3. This will leave all odd numbers of the form 6K+-1 in PT, and you can group these naturally into pairs (6k-1,6k+1). After that, it's basically the standard sieving algorithm, but whenever you remove a nonprime, you also remove its "twin". You have to keep track of these removed twins since you have to do the sieving with them too, and that's what that NT set is for.
@Rudy
you're missing (3,5) and (5,7) in that list