Is there any infinite set of primes for which membership can be decided quickly?
Solution 1:
This is not really my answer. Being vastly ignorant on such matters, I asked Carl Pomerance who replied :
Pintz, Steiger, and Szemeredi did this some time ago, and a paper of mine with Konyagin went further. This is all pre-AKS. My paper with Konyagin is #111 on my home page, and the PSS paper is referenced. Basically all you want are primes p with a large smooth divisor of p-1.
Best wishes, Carl