Take a look at “illegal numbers” https://en.wikipedia.org/wiki/Illegal_number

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There’s the concept of “illegal numbers”, which means that there are technically numeric representations of images or copyrighted material that you can’t know/possess without breaking a law. But the law is subjective which is why we have judges and juries to apply judgement to whether having a large number written on a piece of paper is equivalent to possessions illegal material.

And don't forget random number generators. They are just evil sometimes.

It is amazing that the output of a random number generator can be considered a core part of a DMCA-style 'illegal to work around' anti-circumvention solution.