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Errata 163573

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This commit is contained in:
Andreas M. Antonopoulos 2018-03-14 10:52:52 -06:00
parent 078489e70a
commit 79434212d6
1 changed files with 18 additions and 11 deletions
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@ -605,33 +605,40 @@ 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: The formula to calculate the difficulty target from this representation is:
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target = coefficient * 2^(8 * (exponent – 3)) target = coefficient * 2^(8*(exponent–3))^
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Using that formula, and the difficulty bits value 0x1903a30c, we get: Using that formula, and the difficulty bits value 0x1903a30c, we get:
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target = 0x03a30c * 2^(0x08 * (0x19 - 0x03))^
=> target = 0x03a30c * 2^(0x08 * 0x16)^
target = 0x03a30c * 2^0x08*(0x19-0x03)^
=> target = 0x03a30c * 2^(0x08*0x16)^
=> target = 0x03a30c * 2^0xB0^ => target = 0x03a30c * 2^0xB0^
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which in decimal is: which in decimal is:
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=> target = 238,348 * 2^176^ => 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 => target = 22,829,202,948,393,929,850,749,706,076,701,368,331,072,452,018,388,575,715,328
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switching back to hexadecimal: switching back to hexadecimal:
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=> target = 0x0000000000000003A30C00000000000000000000000000000000000000000000 => target = 0x0000000000000003A30C00000000000000000000000000000000000000000000
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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. 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.