Then what method do the Bitcoin users use to find the (sufficiently short) preimage of the hash values they are working, if indeed the problemspace is that big and sha256 is designed so that the mapping from the output to the input is as complex as possible?
And is it possible for a user to generate Bitcoins faster by discovering a better algorithm for inverting sha256 hashes?
I must be missing something. Why do you think they are inverting the hashes?
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