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You don't seem to have read a lot first in this thread, did you?All puzzles which are multiples of 5 have their public key deliberately exposed. Only for those you could use methods like Kangaroo. Next unsolved in this category is puzzle #135 which still needs computing power expensive enough that is's likely in the ballpark of the puzzle's prize, of course depending on how fast the solver wants to solve it. (I haven't done the calculation, it's an educated guess and depending how "lucky" one could be).
Unsolved Puzzle #71 and onward, not divisible by 5 has no exposed public key, so you can only scan the key space by any brute-force method you deem fit or "more successful" than simple scanning from one end or another (there seems to be no superior method from my humble understanding, but you can believe what you want).
Thanks for the answer Cricktor. I saw that, I was a bit confused about the fact that P2PKH keys are public and honestly did not really understand at first that it is merely a hash and not the public key itself. Still lots of learning to do, I don't expect I'll ever be able to solve one of the keys but this seemed like a fun challenge and wanted to get in on the fun.
So I'm guessing for all the puzzles that aren't solved people use VanitySearch or Bitcrack? Vanitysearch site seems to be down though, where can one find it now ? Anyway, thanks again for the answer

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