Bitcoin Forum

Is there a reason why some people send small amounts of bitcoin to those addresses?

Puzzle 64: 16jY7qLJnxb7CHZyqBP8qca9d51gAjyXQN (https://www.blockchain.com/btc/address/16jY7qLJnxb7CHZyqBP8qca9d51gAjyXQN)

Puzzle 66: 13zb1hQbWVsc2S7ZTZnP2G4undNNpdh5so (https://www.blockchain.com/btc/address/13zb1hQbWVsc2S7ZTZnP2G4undNNpdh5so)

Because it is possible. There are many different puzzles and some of them are sometimes funded. For example this one: bc1qt2mdkehmphggajer3ur3g8l754scj4fdrmw3rn (https://bitcointalk.org/index.php?topic=5282911.msg56567378#msg56567378)

I think JasonSato is talking about these dust amounts, not the puzzle rewards.

If that's the case, most do it to advertise themselves. Stating messages in the blockchain is an expensive way to advertise and I don't think there's a major benefit. Check: https://bitcointalk.org/index.php?topic=5149678.0

Guess what, they are also present on testnet3, check mmFVQtRHbz2MyQ3bYkMWfXnUV4cP6es91m and miWYJkVaKXJroYbBB8kkrBHEecy5dxNKJP.

I know, but the answer is the same: people do that, because it is possible. It is especially true in test networks, where coins are moved here and there, just to see if something is possible or not, or just for fun.

But, this doesn't answer on why they're doing it, or at least not accurately. Anything that is possible on the Bitcoin network can be answered same like. Why do people consolidate their outputs? Because it's possible. Why do they use SegWit? Because it's possible. Why do they run a full node? Because it's possible.

But, this isn't a test network. That's real, hard, globally-traded money. If they want to test something they can use the testnet. They must neither do it for fun. Advertising URLs is the best reason I can think of, which mustn't be effective.

Yes, but sometimes there is no other reason than that.

Calm down, all transaction puzzles started, because people were just curious, how things work and what can be done on Bitcoin. There are many puzzles out there, you can sometimes hit something very easy, for example bc1p0xlxvlhemja6c4dqv22uapctqupfhlxm9h8z3k2e72q4k9hcz7vqzk5jj0, which is just the first public key, encoded as P2TR.

Yes, that's what I meant.
Thanks for your good explanation.

Depending on the amount that is sent to the puzzle address, it could be to increase the incentive to solve the puzzle. Sometimes there is something you are curious whether the problem can ever be solved if people put some effort into it and we know the effort sometimes costs money and there has to be a reward big enough waiting for them to get enough people working on the solution.

But when the amount is tiny and close to dust, it is as @BlackHatCoiner said they are spam-advertising.

1. Create a puzzle that no one is able to solve.
2. Fund the underlying address with a little bit of Bitcoin.
3. Deposit more Bitcoin to it as an added incentive.
4. Find sponsors and people willing to fund it further or hope someone will for whatever the reason.
5. After some time, take all the coins and leave.
6. Thank you for the free Bitcoin you sent me.

The end.

You are right, when we talk about many existing puzzles. But it is also possible to improve that puzzles and make it in a way, where even the creator will have no access to the keys, without solving that challenge. So, when it comes to that famous N-bit private keys, it is true that someone made it, and we can only trust that creator, because there is no range proof, there is no "general script for any matching key".

However, things can be improved over time. Some examples of what could be possible:

Pay to public key:
Output: <pubkey> OP_CHECKSIG
Input: <signature>

Pay to vanity public key:
Output: <pubkeySuffix> OP_CAT OP_CHECKSIG
Input: <signature> <pubkeyPrefix>

Pay to public key hash:
Output: OP_DUP OP_HASH160 <address> OP_EQUALVERIFY OP_CHECKSIG
Input: <signature> <pubkey>

Pay to vanity address:
Output: OP_TOALTSTACK OP_DUP OP_HASH160 OP_FROMALTSTACK <hashSuffix> OP_CAT OP_EQUALVERIFY OP_CHECKSIG
Input: <signature> <pubkey> <hashPrefix>

Another solution is to stick with what we have, and build some homomorphic encryption on top of that, with no consensus changes. Then, it may be possible to create a puzzle, where even the creator knows nothing about the keys, but after applying some operations (like modulo or taking N bits) it could be possible to guarantee that the solution is in some predefined range. When it comes to existing puzzles, their creators could add some range proof for that, it would be a good idea if it would not make it much easier to solve.