Primitive-root primes

The quantity is the power $a$ in the lower bound $c_bx/(\log x)^a$ for primitive-root primes in $(x,2x)$, for the same admissible integer base $b$. A lower power is better.

OpenAI baseline: $2$, released Oct 6, 2:58 PM PT.

These results are Claimed: their authors published them, and we have not checked them.