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Re: Problem 075
Posted: Sat Jan 10, 2015 6:47 am
by solarmew
Is the answer <50,000?
Re: Problem 075
Posted: Sat Jan 10, 2015 9:18 am
by hk
No
Re: Problem 075
Posted: Sat Jan 10, 2015 4:32 pm
by solarmew
didn't think so T.T ...
I got 62444, but it was wrong

Could I pm someone my code? I think I'm just not getting all of them...
Re: Problem 075
Posted: Sat Jan 10, 2015 8:09 pm
by hk
Perhaps you can study the pdf for problem 9 first.
Re: Problem 075
Posted: Sat Jan 10, 2015 9:36 pm
by solarmew
hk wrote:Perhaps you can study the pdf for problem 9 first.
I don't understand the paragraph after eq 9.3
I implemented those conditions, but i'm getting that m<k<2m is always false :\
Re: Problem 075
Posted: Sun Jan 11, 2015 1:46 am
by dawghaus4
Just some observations:
m > n > 0
m < m + n < m + m = 2m
Since k = m + n,
m < k < 2m
And a question:
If you are "running" loops, are you keeping n < m?
Re: Problem 075
Posted: Sun Jan 11, 2015 4:02 am
by solarmew
I define n as n = k - m, like it says in the pdf, so yeah, it should be <m
but before that I pick m from a list of divisors of the perimeter/2, like it says, and then k from a list of odd divisors of p/(2m).
And it so happens that for p = 100, k is never between m and 2m >.> ...
Re: Problem 075
Posted: Sun Jan 11, 2015 9:21 am
by hk
Eh,
Problem 9 (
View Problem) says a+b+c=1000.
Re: Problem 075
Posted: Sun Jan 11, 2015 1:39 pm
by solarmew
Is the method not generalizable to any p?

Re: Problem 075
Posted: Sun Jan 11, 2015 1:57 pm
by dawghaus4
solarmew wrote:
Is the method not generalizable to any p?

Yes, but there are not always unique integral solutions. There can be multiple solutions or no integral solutions, at all.
Problem 75 states this.
In contrast, some lengths of wire, like 20 cm, cannot be bent to form an integer sided right angle triangle, and other lengths allow more than one solution to be found; for example, using 120 cm it is possible to form exactly three different integer sided right angle triangles.
Your result indicates that there are no right triangles with perimeter = 100, whose sides are all integers.
Tom
Re: Problem 075
Posted: Tue Feb 24, 2015 8:27 pm
by Oliver1978
EnDorphin wrote:Alright, I figured out what I did wrong for the one before and I fixed it, but still not correct.
So I wanted to check my new values.
If we let X(n) be the function which gives the number of solutions for the problem when L <= n,
then for L = 50, 100, 500 and 2000, I get these values:
X(50) = 6
X(100) = 11
X(500) = 56
X(2000) = 210
If these are still wrong, could I may be PM anyone the L values for when the max length is 2000?
If these values are all correct, then could someone take a look at my code? It's in Java
I get the same for 50 and 100. But I get 59 for X(500) and 222 for X(2000)

I'm wondering if at least one of us is right with their numbers...
Re: Problem 075
Posted: Tue Feb 24, 2015 8:44 pm
by Georg
leghorn wrote:I'm wondering if at least one of us is right with their numbers...
You are right.
Re: Problem 075
Posted: Tue Feb 24, 2015 9:03 pm
by Oliver1978
So far so good, but my result of xx446 won't work. Maybe someone could give a yes or no for X(135,000) = 14774?
Re: Problem 075
Posted: Tue Feb 24, 2015 9:11 pm
by Georg
I give a "Yes".
Re: Problem 075
Posted: Tue Feb 24, 2015 9:34 pm
by Oliver1978
Vielen Dank. My code is going wrong somewhere. Now I've got to find out where.
Re: Problem 075
Posted: Sat Oct 28, 2017 1:27 am
by MadPat
I agree with Oliver 1978.
X(50) = 6
X(100) = 11
X(500) = 59
X(2000) = 222
Re: Problem 075
Posted: Sat Oct 23, 2021 5:22 pm
by Kamiccolo
*sigh* this is the one problem, which is considered easy, but still too long lasting for me
Unfortunate, getting the same numbers up to X(2000) -.-
EDIT:
oh, the reason being... 150 000 used as a limit instead of 1 500 000
