N, & N-1 are your solutions.
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If it were pig latin, I would think they're talking about the trap-door function, but who is to really know? Hashes by definition are non-reversable one-way 'trapdoor' functions. SHA256(N) -> H, you can calculate H from N, you can only go forward. Impossible by definition to get N from H.
The goal of 'mining' is to be the first to find 'N' leading zeros in the target-hash, nothing about less than or equal
Or perhaps their talking about finding the target hash with more leading zeros than the accepted hash by consensus, this stuff was done years ago, study 'orphan blocks'
The best bet is to go to CHINA, join the CCP, and get on the team that decides what software all the miners are running, and then enter your consensus rules into the source and have it send all the blocks to your address. making money from btc in 2021