arno/bitcoinbook
1
0
Fork 0
mirror of https://github.com/bitcoinbook/bitcoinbook synced 2025-01-11 00:01:03 +00:00
Code Issues Releases Wiki Activity

Edited ch10.asciidoc with Atlas code editor

Browse Source
This commit is contained in:
kristen@oreilly.com 2018-03-14 10:42:38 -07:00
parent 9cd4be7e55
commit a68ca9165f
1 changed files with 23 additions and 25 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
ch10.asciidoc
View File

@ -605,40 +605,38 @@ As you can see, there are a lot of zeros at the beginning of that target, meanin
The formula to calculate the difficulty target from this representation is:
target = coefficient * 2^(8*(exponent–3))^
++++
<ul class="simplelist">
<li>target = coefficient * 2<sup>(8*(exponent–3))</sup></li>
</ul>
++++
Using that formula, and the difficulty bits value 0x1903a30c, we get:
target = 0x03a30c * 2^0x08*(0x19-0x03)^
=> target = 0x03a30c * 2^(0x08*0x16)^
=> target = 0x03a30c * 2^0xB0^
++++
<ul class="simplelist">
<li>target = 0x03a30c * 2<sup>0x08*(0x19-0x03)</sup></li>
<li>=> target = 0x03a30c * 2<sup>(0x08*0x16)</sup></li>
<li>=> target = 0x03a30c * 2<sup>0xB0</sup></li>
</ul>
++++
which in decimal is:
=> target = 238,348 * 2^176^
=> target = 22,829,202,948,393,929,850,749,706,076,701,368,331,072,452,018,388,575,715,328
++++
<ul class="simplelist">
<li>=> target = 238,348 * 2<sup>176</sup></li>
<li>=> target = 22,829,202,948,393,929,850,749,706,076,701,368,331,072,452,018,388,575,715,328</li>
</ul>
++++
switching back to hexadecimal:
=> target = 0x0000000000000003A30C00000000000000000000000000000000000000000000
++++
<ul class="simplelist">
<li>=> target = 0x0000000000000003A30C00000000000000000000000000000000000000000000</li>
</ul>
++++
This means that a valid block for height 277,316 is one that has a block header hash that is less than the target. In binary that number must have more than 60 leading bits set to zero. With this level of difficulty, a single miner processing 1 trillion hashes per second (1 terahash per second or 1 TH/sec) would only find a solution once every 8,496 blocks or once every 59 days, on average.