user12767: I am just developing and testing Bitcoin mining application in plain Javascript
(slow but can be run off-line).
To test it to work correctly I need to download Bitcoin block headers
from Blockchain.info , 6 input parameters .
Are you aware how to call Blockchain API 
https://blockchain.info/api/blockchain_api
I don't use Bitcoin address, no other mining app, just need to download
a number block headers from hashed blocks.
Any idea, demo, example or csv file coming with 6 input parameters
as described in Bitcoin hashing algorithm
https://en.bitcoin.it/wiki/Block_hashing_algorithm

user6990: You can download the blockchain headers using ElectrumX. The data is binary packed, but can be deserialized easily enough. You seem to be trying to solo mine, which is a bad idea at the best of times, let alone with JavaScript. You also seems to be trying to build a SPV client. An easier way would just be to use https://blockchain.info/latestblock to get the lastblock hash and use that.

12767: <p>I am just developing and testing Bitcoin mining application in plain Javascript
(slow but can be run off-line).</p>

<p>To test it to work correctly I need to download Bitcoin block headers
from Blockchain.info , 6 input parameters .</p>

<p>Are you aware how to call Blockchain API 
<a href="https://blockchain.info/api/blockchain_api" rel="nofollow">https://blockchain.info/api/blockchain_api</a></p>

<p>I don't use Bitcoin address, no other mining app, just need to download
a number block headers from hashed blocks.</p>

<p>Any idea, demo, example or csv file coming with 6 input parameters
as described in Bitcoin hashing algorithm</p>

<p><a href="https://en.bitcoin.it/wiki/Block_hashing_algorithm" rel="nofollow">https://en.bitcoin.it/wiki/Block_hashing_algorithm</a></p>
 6990: <p>You can download the blockchain headers <a href="https://electrumx-spesmilo.readthedocs.io/en/latest/protocol-methods.html#blockchain-block-header" rel="nofollow noreferrer">using ElectrumX</a>. The data is binary packed, but can be deserialized easily enough. You seem to be trying to solo mine, which is a bad idea at the best of times, let alone with JavaScript. You also seems to be trying to build a SPV client. An easier way would just be to use <a href="https://blockchain.info/latestblock" rel="nofollow noreferrer">https://blockchain.info/latestblock</a> to get the lastblock hash and use that.</p>
