I want to clear up something important for everyone in this Puzzle journey.
The truth is: prefixes
(whether in Base58 addresses or HASH160) have no relation to the actual private key. Through many experiments step by step till now, I can confirm that once we pass through
the irreversible transformation of elliptic curve multiplication, any hope of tracing back from a prefix to the real private key is gone.

Thinking that a certain prefix gives us a hint about the actual key is just wishful thinking.
The only practical use of prefixes is to measure and track our scanning progress. For example:
Base58 (addresses):Each character = 1 in 58 chance.
Probability of matching n chars = 1 58ⁿ.
In 2³² ≈ 4.29B scans you expect:
1 char ≈ 74M matches
2 chars ≈ 1M matches
3 chars ≈ 22K matches
4 chars ≈ 376 matches
5 chars ≈ 7 matches
6 chars ≈ 1 matches
HASH160 (hex):Each hex digit = 1 in 16 chance.
Probability of matching n digits = 1 16ⁿ.
In 2³² ≈ 4.29B scans you expect:
1 char ≈ 268M matches
2 chars ≈ 17M matches
3 chars ≈ 1M matches
4 chars ≈ 67k matches
5 chars ≈ 4k matches
6 chars ≈ 268 matches
7 chars ≈ 16 matches
8 chars ≈ 1 matches
(On my one RTX 3060 Ti, this 2³² scan finishes in ~2 seconds, and I typically get 1 or 2 addresses with an 8-chars initial HASH160 hex match - sometimes none at all.)
This shows clearly: prefix matching is only a statistical milestone, or a POW, not a clue toward the target private key.
Regarding fixed bits - my own fixed bits formula based on prefix matching is still random - it doesnt inject any new logic or shortcut.
So in the end, prefix-based searching is
just for fun, to keep ourselves engaged while facing the massive challenge of scanning through a 2^71 keyspace.
This puzzle is all about grinding through the natural variance of randomness until we get
lucky. Thats the true nature of brute force.
