Quote from: larry_vw_1955 on Today at 07:42:01 AM

Quote from: PrimeNumber7 on November 08, 2021, 04:22:44 PM

The problem with "inventing" an algorithm with the purpose of generating a private key is that it is difficult to measure how much entropy (security) your private key really has.

Well, i think the chances of someone writing down a random private key that matched my private key would be higher than them being able to design an algorithm that generated my private key given some input. Much higher.

It is not. In base 10, the number 2^256 is 77 digits long. It is well documented that the average person can memorize 7 pieces of information at once. You are not going to be able to reasonably memorize a function that is one out of 2^256 possibilities.

Quote from: larry_vw_1955 on Today at 07:42:01 AM

Quote

If you can think of an algorithm, there is no reason why someone else couldn't think of a similar algorithm.

Not necessarily. There's no reason to think that is the case in general.

People tend to have a bias towards their own experiences. If a function is something you thought of on your own, it is probably not random. If the function is partially the output of a random generator (for example if at one point you multiply your starting number by 5, and "5" is the output of a random generator), your function will be more difficult to memorize.

Quote from: larry_vw_1955 on Today at 07:42:01 AM

Quote from: PN7

Although my recommendation is to create a seed that has 256 bits of entropy, if you insist on creating a brain wallet with low amounts of entropy, I would suggest using an algorithm that is computationally inefficient.

That certainly is one possible feature such an algorithm could have.

Quote from: PN7

Obviously, this assumes that new technology will not be invented that can go from 'brain wallet' phrase to private key more efficiently in the future.

yeah that's not an issue when the algorithm being used to "go from 'brain wallet' phrase to private key" is not known.
they will have to find some other way to crack the bitcoin address. and that's something that all bitcoin addresses would be susceptible to no matter how they were created.

[moderator's note: consecutive posts merged]

I was referring to the algorithm that you may invent that would be computationally expensive.

IMO, the only excuse for having a low entropy input to generate a private key is that it is expensive to go from input to private key.