Problem 218

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mverschaeve
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Clarification for problem 218 request

Post by mverschaeve »

Hi,

Project euler is not accepting my answers for this problem and I can't immediately see a bug in my program or my reasoning so perhaps I have understood the problem wrong.

Some questions:
Are (a=7, b=24 and c=25) and (a=24, b=7 and c=25) considered different perfect right-angled triangles ?
Are degenerate triangles like (a=0, b = 4 and c = 4) considered perfect right-angled triangles, and if so are they super perfect (i guess not, since i consider 0 a multiple of 6 and 28))
Why do they say that a super perfect triangle must have an area being a multiple of 6 and 28? Does that not mean that the area is a multiple of lcm(6,28)=84 ? Or is a perfect triangle allready super perfect is its area is a multipe of 6 OR a multiple of 28 ?

Kind regards,

Michael
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hk
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Re: Clarification for problem 218 request

Post by hk »

Seeing that you only solved 4 problems, why not try others you understand first?
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TripleM
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Re: Clarification for problem 218 request

Post by TripleM »

a, b, and c are not mentioned in the definition of a triangle. Two right angle triangles are equivalent if they have the same sides.

A degenerate triangle is not a triangle.

6 and 28 means 6 and 28 (surprisingly :P), not 6 or 28.
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mverschaeve
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Re: Clarification for problem 218 request

Post by mverschaeve »

TripleM wrote:a, b, and c are not mentioned in the definition of a triangle. Two right angle triangles are equivalent if they have the same sides.

A degenerate triangle is not a triangle.

6 and 28 means 6 and 28 (surprisingly :P), not 6 or 28.
Thanks for the clarification but I solved the problem in the meanwhile.
I had an overflow in my program.
I suppose I got frustrated with the problem and that's why I asked stupid questions.
My apologies to anyone I annoyed with my clarification request.
Kind regards,

Michael
Knut.Angstrom
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Problem 218

Post by Knut.Angstrom »

I should like to have problem 218 defined a bit clearer. I might be wrong but I do not consider the triangle (7,24,25) to be acceptable. Do you say that 84 is a multiple of 6 and 28? I thought that such a number should be
n = 6**s * 28**t
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Tommy137
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Re: Definition in problem 218

Post by Tommy137 »

It means that 6|n and 28|n.
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stijn263
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Re: Definition in problem 218

Post by stijn263 »

28 * 3 = 84 = 6 * 14

So 84 is a multiple of 6 and 28
Konrad127123
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Re: Problem 218

Post by Konrad127123 »

Perhaps I'm being stupid, but I think I've solved this question.

However, when I submit my answer I don't get the success/failure page, but the website takes me straight back to the problem page instead. If I change my answer to something else I *do* get the error page.

Can anyone confirm/deny this or alternatively offer to check my answer?

Thanks,

Konrad
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Georg
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Re: Problem 218

Post by Georg »

Do you suppress sending the referer as described here?
If this does not solve your problem, you can PM me your answer.
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Georg
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Re: Problem 218

Post by Georg »

Konrad127123 wrote:Can anyone confirm/deny this or alternatively offer to check my answer?

Thanks,

Konrad
Your answer is correct.
funktio
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Problem 218

Post by funktio »

Long time no see. 8-)

I have a small suggestion to clarify the wording of Problem 218 (View Problem).
We will call a right angled triangle perfect if
-it is a primitive right angled triangle
-its hypotenuse is a perfect square

We will call a right angled triangle super-perfect if
-it is a perfect right angled triangle and
-its area is a multiple of the perfect numbers 6 and 28.
In both definitions both conditions are necessary, but only the second one has the word "and" between them. For consistency, I think it'd be good to add it to the first definition as well:
We will call a right angled triangle perfect if
-it is a primitive right angled triangle and
-its hypotenuse is a perfect square

We will call a right angled triangle super-perfect if
-it is a perfect right angled triangle and
-its area is a multiple of the perfect numbers 6 and 28.
I've solved 4 problems this week without much difficulty and remember trying each one of them a year ago and failing. I hope to get back to 100% soon. :)
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stijn263
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Re: Problem 218

Post by stijn263 »

Welcome back :)
idantlol
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Re: Problem 218

Post by idantlol »

Would it be possible to have an example of a perfect, not super-perfect right angled triangle?
Last edited by idantlol on Fri Apr 13, 2012 8:48 pm, edited 1 time in total.
TripleM
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Re: Problem 218

Post by TripleM »

They're meant to be quite hard to find - seeing an example would probably be quite a big hint as to the underlying pattern, so I think it's best you keep working on it yourself :)
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