Blockchain transaction

A computer-implemented method of generating a first proof transaction for recording to a blockchain, the method comprising:

• accessing one or more first proof transaction templates, each proof transaction template corresponding to a different one of a sequence of (n+1) verification values ri, wherein 0≤i≤n, each proof transaction template comprising a template first unlocking script and an outpoint identifying a first locking script of a task transaction, the template first unlocking script comprising a public key corresponding to the corresponding verification value;
• deriving one of the sequence of (n+1) verification values ri from (i+1) data values;
• providing, in a first unlocking script of the first proof transaction, the template unlocking script corresponding to the derived verification value and a value based on the derived verification value;
• and
• making the task blockchain transaction available to one or more nodes of a blockchain network.

A computer program embodied on non-transitory computer-readable storage media and configured so as, when run on one or more processors, the one or more processors perform a method of generating a provable task for recording to a blockchain, the provable task for verifying (n+1) data items, the method comprising:

• generating a task blockchain transaction, wherein the task blockchain transaction comprises a first locking script comprising (n+1) subscripts, each respective subscript defining a different unlocking condition corresponding to a knowledge proof, wherein each unlocking condition is satisfied by a different one of a sequence of (n+1) verification values ri, wherein 0≤i≤n, wherein each subscript comprises a public key corresponding to the corresponding verification values satisfying the unlocking condition of the subscript, wherein the respective subscript, when executed with a first unlocking script of a proof blockchain transaction, is configured to verify a verification value provided in the first unlocking script based on the unlocking condition, the verification value ri being derived from (i+1) data values to be verified;
• making the task blockchain transaction available to one or more nodes of a blockchain network;
• generating one or more first proof transaction templates, each first proof transaction template corresponding to a different one of the sequence of verification values, each first proof transaction template comprising a template first unlocking script and an outpoint identifying the first locking script, the template first unlocking script comprising the public key corresponding to the corresponding verification value, wherein the first unlocking script is derived from the template first unlocking script and the corresponding verification value;
• and
• making the one or more first proof transaction templates available to a worker.