I get the idea but I don't think it can work; say you make a list from 0 - 10 million; now that's only 23-24 bits of entropy, but the problem is, even if that list was big enough to be useful, and even if you were examining the raw 'entropy input', (and say the hashing output from that input follows a known algo) the problem is: the set of 32 byte values with only 24 bits of entropy is *not* only the numbers from 1 to 10million (or whatever); it's a vastly larger set (trivial example: highest order bits are filled in, instead of lowest order bits). whether a given output is in that set can be checked with a mathematical calculation, but listing all of them isn't realistically possible.