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Share Your Experience: Take the 2024 Developer Survey
10 votes
Accepted

What is the Block 1,983,702 Problem?

Bitcoin assumes a (txid, vout) pair, usually referred to as an "outpoint", is a unique identifier for a UTxO. This assumption did not actually hold in the early years of Bitcoin, since two ...
Antoine Poinsot's user avatar
7 votes
Accepted

Is it possible for the coinbase transaction in block 164384 to be duplicated in block 1983702?

It would be possible for block 1,983,702 to repeat the coinbase transaction of block 164,384 under these three conditions: The block does not collect any segwit transactions, otherwise a witness ...
Murch's user avatar
  • 75.7k
6 votes
Accepted

What's the smallest possible coinbase transaction / block size?

All transactions, including coinbase transactions must have at least one input and one output. since the output value is encoded in a fixed number of bytes, not claiming the block subsidy does not ...
Antoine Poinsot's user avatar
6 votes
Accepted

When was the first OP_RETURN output in a coinbase?

The first coinbase transaction that has an OP_RETURN output is in block 246816. The transaction has 288 outputs in total, and the OP_RETURN is the last one.
Vojtěch Strnad's user avatar
6 votes
Accepted

Why are miners setting the locktime in coinbase transactions?

Wang Chun of f2pool (@satofishi) said on Twitter: “We repurpose those 4 bytes to hold the stratum session data for faster reconnect.” He went on to say: "The coinbase locktime is set to: ...
bordalix's user avatar
  • 582
6 votes
Accepted

Where was the term "coinbase" first coined, who first used it?

The term "coinbase" was most likely coined by Satoshi through the IsCoinbase method of the CTransaction class. It was both part of the first publicly distributed version of the source code ...
Antoine Poinsot's user avatar
5 votes

Different balances between fullnode and bitcoin explorer

You appear to have searched for a Pay to Public Key Hash (P2PKH) address, but the output on the coinbase transaction of block 200 is a Pay to Public Key (p2pk) output. There is no address standard for ...
Murch's user avatar
  • 75.7k
5 votes
Accepted

Are all transactions, whether SegWit or non-SegWit, part of the commitment in a coinbase transaction?

The wtxids of all transactions are committed to by the witness commitment tree in the coinbase transaction (except the coinbase wtxid itself, as that would be a cyclic dependency). This includes non-...
Pieter Wuille's user avatar
5 votes

Is it possible for the coinbase transaction in block 164384 to be duplicated in block 1983702?

Yes, it is possible for block 1,983,702 to duplicate the coinbase of block 164,384 with the current consensus rules. Starting with block 1,983,702 the explicit BIP30 check will be re-enabled (see this ...
Antoine Poinsot's user avatar
4 votes

What is the Block 1,983,702 Problem?

My understanding of the problem is: The coinbase transaction in block 164384 (3aa03753fc) happens to start with OP_PUSHBYTES_3 d6441e which is the value 1983702. This means there is a very small but ...
delta1's user avatar
  • 113
4 votes
Accepted

Processing bitcoin reward block's input transaction

This is the scriptSig of a coinbase transaction (the first transaction in every block is special; it doesn't actually spend anything but brings new coins into existence). Coinbase transactions have a ...
Pieter Wuille's user avatar
3 votes
Accepted

bitcoin-cli generatetoaddress <numberofblocks> <address> has 2 outputs

Not including the second output would result in a different failure, although it is likely that that check has not been performed yet. The inclusion of that output is necessary if your block contains ...
Ava Chow's user avatar
  • 70.8k
3 votes
Accepted

What fields of a coinbase transaction can be empty?

Would a block be accepted in which the coinbase transaction has an empty input scriptSig field? Is there an example of such? No, for unknown reasons there is a consensus rule that the coinbase input ...
Pieter Wuille's user avatar
3 votes

What is the block maturation time?

We require a maturation period for coinbase outputs, because any two blocks at the same height will condemn at least one coinbase transaction to never exist in the best chain. If users were able to ...
Murch's user avatar
  • 75.7k
2 votes

How can I look at the genesis block raw txn?

The genesis block is a special case. Among other quirks, its coinbase transaction doesn't actually create any spendable outputs, which is why the getrawtransaction RPC treats it as if it doesn't exist....
Vojtěch Strnad's user avatar
2 votes

Is it possible for the coinbase transaction in block 164384 to be duplicated in block 1983702?

If the block contains at least one segWit transaction, the coinbase transaction must have a witness commitment as one of its outputs. Therefore, a miner that wants to reuse the coinbase transaction ...
LeaBit's user avatar
  • 950
2 votes
Accepted

Is a block without transactions valid: also not including a coinbase?

No, consensus rules require a block to have at least one transaction. It also requires transactions to have at least one input and at least one output.
Pieter Wuille's user avatar
1 vote

How to recover bitcoin from Coinbase?

Addresses never expire. Even if you generate hundreds or thousands of new addresses, money sent to an old address in future years will still be under your control, assuming you make backups of your ...
RedGrittyBrick's user avatar
1 vote

How many nodes and edges does the UTXO-coinbase graph have?

Since you indicated in a comment that you are fine with multiple edges representing the same transaction, you get a node for each coinbase transaction and each TXO ever created, and edges to the tune ...
Murch's user avatar
  • 75.7k
1 vote

How to set the output script of coinbase transaction

Bitcoin addresses are standardized human-readable notations for certain classes of specific scriptPubKeys. While there is nothing invalid about scripts outside of these standard forms, there is ...
Pieter Wuille's user avatar
1 vote

What is TXID?Is it used to calculate merkleroot

There are two types of transaction identifiers, TXID and WTXID. TXID represents the result of a double SHA256 of the serialized transaction form without witness data. It is used to uniquely identify ...
LeaBit's user avatar
  • 950

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