4 ms·

This is where common sense comes into play. If you were in front of a judge, your argument that you are just posting a mathematical fact wouldn't stand for more

This is where common sense comes into play. If you were in front of a judge, your argument that you are just posting a mathematical fact wouldn't stand for more than 10 seconds. Tell the truth: why did you choose those two numbers, specifically? Oh, because they allow you to unlock a TI calculator. So (the judge would say), you are publishing a secret key. You are not publishing random number products for the fun of seeing how many digits your calculator can handle. Taken to the extreme, this is the same argument as a hacker saying: I didn't break into the bank's computers, I just wrote a program, and the program is the one that broke into the bank. I was just typing on a keyboard, that's all I did. Intent.

jrockway 17y ago
It is an interesting fact, though, since there is a sequence of integers called "integers factored by computers". This integer is now a member of that set. The fact that a number this large was factored is interesting to the mathematical community. Should this information be suppressed because TI used this number to sign their OS? What if there was a table of all numbers and their factorizations, 1 = 1, 2 = 2, 3 = 3, 4 = 2 * 2, ... If you noticed TI was using a number in this list as their signing key, you could just look it up. Would that be illegal? Then why is it illegal to lazily generate this list as needed? What other properties of integers are illegal to discuss? (FWIW, I am almost certain that the DMCA does not apply to this case, anyway. TI is just sending letters Because They Can and because there is no penalty if they're wrong. I can send you a C&D telling you to take down the above comment. The appropriate response is to mock me, not to take the comment down.) Basically, TI should have used a bigger integer. Why rely on something as flaky as the legal system to protect your business model when you can use mathematical fact instead? (Answer: because using a bigger number would have added 1 cent to the cost of every calculator sold. Sending C&Ds is free.)
- alain94040 17y ago
  You are still playing cute and don't understand how you'll be cut off by a judge (ie., common sense) in seconds. Sir, is that the only large number that you published? Are you saying that your interest in this number has nothing to do with its presence as a key in TI's calculators? How come a search of your house found all those dumps of TI firmware? Seriously? Don't get me wrong, I'm on your side, but this defense is called "playing stupid" and it is known not to work.
  - henning 17y ago
    There might be legal precedent on this issue since there used to be books of tables of logarithms published in the days before calculators and computers. The publishers would place subtle errors in a few random points many digits out to prove that someone else had copied the numbers without computing the logarithms themselves. Of course IANAL.
    - gloob 17y ago
      Forgive me my lack of insight, but I'm not entirely certain what that has to do with this particular case. What you are listing is a mechanism for copyright protection - while the numbers themselves cannot be copyrighted, the book containing them might qualify for copyright (depending on the local legal system). The question here is not about copyright, however. (Probably. Maybe.) The question here is whether it is legal to factor an arbitrary number and inform others of the results.
      - delackner 17y ago
        England and the United States have decided differently (england: yes, us: no) whether to allow copyright of lists of otherwise uncopyrightable information. The long term outcome has been a thought provoking natural experiment: the United States, with no such copyright allowance, has a thriving industry of competing databases of various kinds of publicly available information. The UK has no such thriving ecosystem. Or at least this was all according to a newspaper article a few years back. For all I know they may have since seen the light and banned copyright on databases.
    - jrockway 17y ago
      Copying the table may be illegal (although probably not; you can copy the phonebook), but referring to it while figuring out how to make a flat screwdriver unscrew a phillips-head screw is probably not. How is using a flat screwdriver to unscrew a phillips-head screw different from using your own OS on your own calculator instead of using TI's?
  - jrockway 17y ago

jrockway 17y ago

It is an interesting fact, though, since there is a sequence of integers called "integers factored by computers". This integer is now a member of that set. The fact that a number this large was factored is interesting to the mathematical community. Should this information be suppressed because TI used this number to sign their OS? What if there was a table of all numbers and their factorizations, 1 = 1, 2 = 2, 3 = 3, 4 = 2 * 2, ... If you noticed TI was using a number in this list as their signing key, you could just look it up. Would that be illegal? Then why is it illegal to lazily generate this list as needed? What other properties of integers are illegal to discuss? (FWIW, I am almost certain that the DMCA does not apply to this case, anyway. TI is just sending letters Because They Can and because there is no penalty if they're wrong. I can send you a C&D telling you to take down the above comment. The appropriate response is to mock me, not to take the comment down.) Basically, TI should have used a bigger integer. Why rely on something as flaky as the legal system to protect your business model when you can use mathematical fact instead? (Answer: because using a bigger number would have added 1 cent to the cost of every calculator sold. Sending C&Ds is free.)

alain94040 17y ago
You are still playing cute and don't understand how you'll be cut off by a judge (ie., common sense) in seconds. Sir, is that the only large number that you published? Are you saying that your interest in this number has nothing to do with its presence as a key in TI's calculators? How come a search of your house found all those dumps of TI firmware? Seriously? Don't get me wrong, I'm on your side, but this defense is called "playing stupid" and it is known not to work.
- henning 17y ago
  There might be legal precedent on this issue since there used to be books of tables of logarithms published in the days before calculators and computers. The publishers would place subtle errors in a few random points many digits out to prove that someone else had copied the numbers without computing the logarithms themselves. Of course IANAL.
  - gloob 17y ago
    Forgive me my lack of insight, but I'm not entirely certain what that has to do with this particular case. What you are listing is a mechanism for copyright protection - while the numbers themselves cannot be copyrighted, the book containing them might qualify for copyright (depending on the local legal system). The question here is not about copyright, however. (Probably. Maybe.) The question here is whether it is legal to factor an arbitrary number and inform others of the results.
    - delackner 17y ago
      England and the United States have decided differently (england: yes, us: no) whether to allow copyright of lists of otherwise uncopyrightable information. The long term outcome has been a thought provoking natural experiment: the United States, with no such copyright allowance, has a thriving industry of competing databases of various kinds of publicly available information. The UK has no such thriving ecosystem. Or at least this was all according to a newspaper article a few years back. For all I know they may have since seen the light and banned copyright on databases.
  - jrockway 17y ago
    Copying the table may be illegal (although probably not; you can copy the phonebook), but referring to it while figuring out how to make a flat screwdriver unscrew a phillips-head screw is probably not. How is using a flat screwdriver to unscrew a phillips-head screw different from using your own OS on your own calculator instead of using TI's?
- jrockway 17y ago