First, a question: is there something similar for other blockchains? And, a clarification, when I said public keys I referred to public keys that match an unknown private key but I understand now (am I correct?) that this puzzle is purely brute forcing private keys with a lot of zeroes and then matching with the addresses in the blockchain (which would be a function from the public key).
I don't know if other blockchains have these puzzles. You are correct thas this puzzle is brute forcing private keys with a bunch of zeroes, from which a public key can be calculated.
