Almost the exact same idea as bit-flip-2, except
1. We need to find a bitcoin hash that matches the strong prime requirement, which just took longer
2. We need to speed up the program because we hit the 30 minute timeout due to the longer primegen

Speeding up the solver can be done by noticing that in the case where the k+1th bit is 1, in the next loop we can reuse one of the requests, meaning we save 25% of requests and sqeak in just barely under the time limit

Original writeup (https://ubcctf.github.io/2020/11/dragonctf2020-bitflips/).