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Harvard mathematician answers 150-year-old chess problem

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Re: Harvard mathematician answers 150-year-old chess problem

#21
post #18

It does make me chuckle the way this is reported. We answered this problem! Ok what's the answer "well about (0.143n)^n". I've figured out the value of Pi! It's about 3. Firstly, that's not an answer that's's an approximate answer, and secondly, it's wrong for a practical values of n. I really don't have the mentality of a mathematician.

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Re: Harvard mathematician answers 150-year-old chess problem

#22
post #18

It does make me chuckle the way this is reported. We answered this problem! Ok what's the answer "well about (0.143n)^n". I've figured out the value of Pi! It's about 3. Firstly, that's not an answer that's's an approximate answer, and secondly, it's wrong for a practical values of n. I really don't have the mentality of a mathematician.

No post body was provided.

Re: Harvard mathematician answers 150-year-old chess problem

#25
post #18

It does make me chuckle the way this is reported. We answered this problem! Ok what's the answer "well about (0.143n)^n". I've figured out the value of Pi! It's about 3. Firstly, that's not an answer that's's an approximate answer, and secondly, it's wrong for a practical values of n. I really don't have the mentality of a mathematician.

You say "practical values of n", but the answer to n = 27 is already known and I would be very surprised if the final result had any practical application. The point of these problems is rarely the numerical answer, but the development of new techniques: The problem of determining the asymptotic growth of this number is studied because it is a good playground for sharpening mathematical tools and methods. In this sense, the asymptotic problem is an interesting one, and it was solved. Now that the main term is characterized, people can investigate sharper estimates.

The problem of determining an efficient algorithm for every n, on the other hand, is just hopeless, which means that it is not interesting for the purpose I described above. Studying "small" n (up to 40, say) is not useless, though, if it leads to algorithmic breakthroughs (in SAT solving, for example). It is, however, an "orthogonal" problem, in the sense that it requires a completely different set of techniques.

To illustrate my point: If the answer for n = 50 appeared out of nowhere, would people care about the number itself? I bet people would be much more interested in how it was done.

Re: Harvard mathematician answers 150-year-old chess problem

#27
post #18

It does make me chuckle the way this is reported. We answered this problem! Ok what's the answer "well about (0.143n)^n". I've figured out the value of Pi! It's about 3. Firstly, that's not an answer that's's an approximate answer, and secondly, it's wrong for a practical values of n. I really don't have the mentality of a mathematician.

Given the number of significant digits, the answer is closer to stating that pi is approximately equal to 3.14

I agree, you don't have the mentality of a mathematician.

Re: Harvard mathematician answers 150-year-old chess problem

#28

Earlier quoted context omitted.

It's little o notation. It does not depend on n. For example x^2 is in O(x^2) but is not in o(x^2).

When used in that equation it's meant to implicitly depend on n as edflsafoiewq points out. o(1) stands for o(f(n)) where f(n) = 1. Hence any function g(x) in the family of functions represented by o(1) must be less than c * f(x) for every positive c and all x greater than some m. This is exactly the statement that any function in the family of functions o(1) must tend to zero. Whenever you see big-O/little-O/theta n…

I think a nuance people are missing is that for big O, it is sufficient for the existence of any positive C and x, but for small o there must always exist an x for every c.
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