#bitcoin: started thinking where the 21 million and halvening every 210 thousand blocks comes from. This doesn't answer the question wholly (why 4 years etc.), but it's interesting anyway. Is there any better known explanation to this?
"Here's a mathematical explanation:
Calculate the number of blocks per 4 year cycle:
6 blocks per hour
* 24 hours per day
* 365 days per year
* 4 years per cycle
= 210,240
~= 210,000
Sum all the block reward sizes:
50 + 25 + 12.5 + 6.25 + 3.125 + ... = 100
Multiply the two:
210,000 * 100 = 21 million."
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