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If you think it's not a lame mathematical trick, would you care to say how you think it's done? Or at least, say something that makes it clear to those who kno
by RiderOfGiraffes 17y ago
If you think it's not a lame mathematical trick, would you care to say how you think it's done? Or at least, say something that makes it clear to those who know how it's done that you also know the answer? Like, for example, tell us how it can go wrong.
Although I'm not actually involved in this event, it is the sort of thing that I follow closely, and on other occasions am involved in. I am especially interested to discover what people already know so I can avoid well-known, obvious or boring stuff, and produce things that are more challenging.
- sfk 17y agoI suspect they couldn't do much with 0000000, where the first digit that is chopped off is my secret digit. I was under the impression that this trick usually involves the difference of two numbers with the same digits.
- pbhjpbhj 17y agoWell Benford's law says it's more likely to be a 1 but the rest of it falls into the 5% failure rate they're allowing. Also from my skim of the rules I think you have one to many zeros.
- pbhjpbhj 17y agoTo get it exactly right would be luck, they're going for 95% correct. Tables. They're limiting the search space considerably in the setup (I skimmed) such that it appears you're supplying random numbers to them but they're quite narrowly defined and all but one of the digits provides enough of a key to lookup the last digit. For example in the range (1000000,1000040) only 1000000 can be produced from multiplying single digits; there are 4 primes in that range FWIW. Add in some test data, and perhaps something like Benford's law and bobs your uncle. FWIW, I'm not telling you it's obvious, nor that you have to think it's lame too.
- RiderOfGiraffes 17y agoWould it impress you more to know that I can this trick live and without assistance?
- pbhjpbhj 17y agoYes.