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42 is found to be the sum of three cubes

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Re: 42 is found to be the sum of three cubes

#51

Post by yati »

mombul wrote: post #27

Yeah but now, what? What was learned from this? Why did we look for a solution in the first place? How is it important that a number can be a sum of three cubes?

There are others in this thread who are curious too, e.g.:

> Could someone elaborate on why this is interesting? The linked page doesn't have much context.

Just compare your question's tone with that, for example, and maybe that will explain why you're being downvoted [I did not, but I get why others are -- you deleted your other comment "Thanks for the downvotes..."]

Re: 42 is found to be the sum of three cubes

#54

Post by Tuna-Fish »

whitehouse3 wrote: post #39

Why doesn't this evaluate in Excel? =(-80538738812075974)^3 + 80435758145817515^3 + 12602123297335631^3 Returns 1.09785E+36

Because the numbers cubed are way larger than the numbers that Excel can represent precisely. Excel uses 64-bit IEEE 754 floats for all arithmetic. They can be used to accurately describe integers smaller than 2^53, or ~10^16. The first number cubed is ~-5*10^50, so you are very clearly outside the range where excel is precise.

You should not use Excel to do any serious mathematics, or really anything else where numerical precision is important.

Re: 42 is found to be the sum of three cubes

#56

Post by sp332 »

scrungus wrote: post #35
mombul wrote: post #27

Yeah but now, what? What was learned from this? Why did we look for a solution in the first place? How is it important that a number can be a sum of three cubes?

If you can break up a reasonably-sized table (perhaps 120 or so) of numbers into their respective sums of cubes, breaking many types of encryption is arbitrary.

Guessing you meant "trivial". Do you have some info about how this helps break encryption?

Re: 42 is found to be the sum of three cubes

#57

Post by qntty »

mombul wrote: post #27

Yeah but now, what? What was learned from this? Why did we look for a solution in the first place? How is it important that a number can be a sum of three cubes?

Math is done for it's own sake. Read this article if you want to know more about people trying to spell out of justification for this.

https://www.theparisreview.org/blog/2019/07/22/the-aesthetic...

Re: 42 is found to be the sum of three cubes

#59

Post by sp332 »

techolic wrote: post #2

See also https://twitter.com/robinhouston/status/1169877007045296128 . I was prompted the twitter link has been submitted but wasn't able to find it. Edit: And apologies for using unicode ㊷ in the title, the ascii 42 was removed from the title after initial submission.

The title is sanitized on first submission, but you can edit the title afterward and put it back in. This works with some punctuation that gets cleaned out too.
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