Problem 353

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BostonBear
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Problem 353

Post by BostonBear » Sun Oct 09, 2011 3:31 am

I am a little confused about the new problem. This sphere has integer coordinates. Yet we are not given a specific size, so as far as I can tell , for a generic r, there are only 6 integer coordinates. (r,0,0), (0,r,0), (0,0,r) and its antipodals. Is there something I'm missing here? Does each trip to a station have to be a direct trip, or can you change directions before you get to the next station?

Edit, never mind, I figured out what I was not seeing right
Last edited by BostonBear on Sun Oct 09, 2011 4:36 am, edited 1 time in total.

TripleM
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Re: Euler Problem 353

Post by TripleM » Sun Oct 09, 2011 4:20 am

You are given a specific size - r is equal to 2^n - 1 for each value of n from 1 to 15.

cyrillic
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Euler Problem 353

Post by cyrillic » Wed Oct 12, 2011 10:33 am

Could I check with someone the value of M(r) for n=15 I'm getting, to validate my code? Cheers.

thundre
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Re: Euler Problem 353

Post by thundre » Wed Oct 12, 2011 2:16 pm

cyrillic wrote:Could I check with someone the value of M(r) for n=15 I'm getting, to validate my code? Cheers.
PM it to me and I'll tell you whether it matches mine.
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Arthelais
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Re: Problem 353

Post by Arthelais » Sun Dec 13, 2015 8:17 pm

Could someone verify for me whether M(1000) is equal to 0.05174553024? I feel like I am facing a rounding error and I can't seem to figure it out.

MuthuVeerappanR
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Re: Problem 353

Post by MuthuVeerappanR » Mon Jun 05, 2017 10:29 am

Is this problem prone to precision errors?? I tried a couple of methods and they all provide the same for value upto M(10). But somehow my answer is not getting accepted.
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sjhillier
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Re: Problem 353

Post by sjhillier » Thu Jun 08, 2017 1:13 pm

Well you certainly have to be precise, but no more so than many other problems. There are other possible error modes, but it would be wrong to say more.

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Re: Problem 353

Post by MuthuVeerappanR » Thu Jun 08, 2017 1:34 pm

Thanks sjhillier. I solved it yesterday. Turns out one of my assumptions only fails for the k = 8 case.
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sjhillier
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Re: Problem 353

Post by sjhillier » Thu Jun 08, 2017 6:38 pm

MuthuVeerappanR wrote:
Thu Jun 08, 2017 1:34 pm
Thanks sjhillier. I solved it yesterday. Turns out one of my assumptions only fails for the k = 8 case.
I'm sure I made the same mistake too.

bleh0.5
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Re: Problem 353

Post by bleh0.5 » Tue Aug 14, 2018 4:57 pm

Are we supposed to calculate every single integer set of coordinates or are the only coordinates going to be (0,r,r) and stuff like that

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RobertStanforth
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Re: Problem 353

Post by RobertStanforth » Tue Aug 14, 2018 6:56 pm

bleh0.5 wrote:
Tue Aug 14, 2018 4:57 pm
Are we supposed to calculate every single integer set of coordinates or are the only coordinates going to be (0,r,r) and stuff like that
The admissible paths (from which you are asked to find the one with the lowest risk) are permitted to use any of the integer-coordinate points on the surface of $C$. The problem statement does not confine you to a special subset of them.

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