3 ms·
Mentioned in another comment here, but you're describing hashcash: https://en.wikipedia.org/wiki/Hashcash https://en.wikipedia.org/wiki/Hashcash
by tyingq 5y ago
Mentioned in another comment here, but you're describing hashcash: https://en.wikipedia.org/wiki/Hashcash https://en.wikipedia.org/wiki/Hashcash