Search found 545 matches

by jaap
Sat Jun 24, 2017 10:19 pm
Forum: News, Suggestions, and FAQ
Topic: Suggestion: Searching Problems
Replies: 4
Views: 2209

Re: Suggestion: Searching Problems

Also when you're logged in, on the archived problems page is a link to see the details of all the problems on one page. Then you can use ctrl-F in your browser to search the text.
by jaap
Fri Jun 09, 2017 3:08 pm
Forum: Combinatorics
Topic: Expected Value and Multiple Integrals
Replies: 4
Views: 7680

Re: Expected Value and Multiple Integrals

Say, If have $\mathbb{E}(f(x, y))$. Then is there a easier way to find any of $\mathbb{E}(f(a - x, y))$, $\mathbb{E}(f(x, m a - y))$, or $\mathbb{E}(f(a - x, m a - y))$?? No. $\mathbb{E}(f(x, y)|(x,y) \in T)$ is the expected value that $f$ has within the triangle $T$, which is bounded by the lines ...
by jaap
Fri Jun 09, 2017 9:24 am
Forum: Combinatorics
Topic: Expected Value and Multiple Integrals
Replies: 4
Views: 7680

Re: Expected Value and Multiple Integrals

I'm no expert on this, but I think it is correct. Basically, you have a sample space consisting of the points in the 2-dimensional plane $\Bbb R^2$, and a uniform Probability density function which has the value $\frac{2}{ab}$ for every point inside the triangle $T$, and $0$ outside of it: $$pdf(P) ...
by jaap
Tue May 16, 2017 7:43 pm
Forum: News, Suggestions, and FAQ
Topic: Errors/Warnings/Bugs
Replies: 577
Views: 166213

Re: Errors/Warnings/Bugs

Obergscheidle wrote: Tue May 16, 2017 6:51 pm As of now, the statistics page seems not to work, it has no content, except for header and footer.
Thanks in advance for fixing it.
I have the same problem. Also, the Friends page takes a very long time to load.
by jaap
Tue Apr 04, 2017 8:31 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 367
Replies: 11
Views: 4813

Re: Problem 367

I suspect I get wrong values only in case of k = 2. Any help is greatly appreciated. I suspect that your k=2 case is that you pick two numbers, and randomly permute them, i.e. 50% that they swap and 50% that they don't. This makes your results twice what they should be if you always swap the two ra...
by jaap
Tue Jan 17, 2017 10:08 am
Forum: News, Suggestions, and FAQ
Topic: Errors/Warnings/Bugs
Replies: 577
Views: 166213

Re: Errors/Warnings/Bugs

You have a bug in the confirmation check - many times I enter correct numbers but the system rejects me. Here is an example: The captcha remains valid for a limited time. If the problem page has been open for a while, the captcha will have expired and hence fail even if you enter the right number. ...
by jaap
Fri Jan 06, 2017 11:38 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 103
Replies: 38
Views: 13083

Re: Problem 103

When is the conditional "if p, then q" true? If the hypothesis is false, the conditional is true. (Note: that does not say, when p is false, q is true.) Thus, {1} vacuously satisfies the conditional. Interpret the conditional this way, "Whenever you have two nonempty disjoint subsets, the following...
by jaap
Thu Jan 05, 2017 12:17 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 081
Replies: 11
Views: 4968

Re: Problem 081

srinathmkce wrote:Can someone correct my understanding ?
I sent a private message with some explanation.
by jaap
Tue Jan 03, 2017 2:47 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 584
Replies: 9
Views: 3967

Re: Problem 584

Could you add it to the problem statement that wrap-around possibilities must be considered? I found an article on the net which mentioned this, and so, I asked this question, otherwise, I would have never been able to guess that wrap-around possibilities should be considered. I don't think that ne...
by jaap
Thu Aug 25, 2016 3:34 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 445
Replies: 10
Views: 4543

Re: Problem 445

1)The problem states : "f(a,b,n) is retraction if ... " . Does it mean :" f(a,b,n) for x is retraction if ..." ? For any a,b,n, we have a function f a,b,n . It is a function of x. Being a retraction is a property of the function as a whole. 2) Suppose "the retraction for n" is known. Now, what is t...
by jaap
Thu Jul 28, 2016 8:35 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 566
Replies: 7
Views: 4580

Re: Problem 566

I understand that 9≤a<b<c≤n are the bounds for the summation, but I've never seen one with multiple variables before so I'm not certain I understand how it works. Does it mean that for a particular value of n, I sum up F(a,b,c) for every possible value of a, b, and c that satisfies those bounds? E....
by jaap
Mon Jul 18, 2016 7:18 am
Forum: News, Suggestions, and FAQ
Topic: How often is the "profile image" updated?
Replies: 5
Views: 2109

Re: How often is the "profile image" updated?

For me it says 55 solved.
by jaap
Wed Jun 01, 2016 10:54 am
Forum: Combinatorics
Topic: Partitions with a unique maximum part
Replies: 4
Views: 8267

Re: Partitions with a unique maximum part

The only definition of mode that I know is "the value that appears most often in a set of data" but that is clearly not what you mean here.
by jaap
Tue May 10, 2016 6:15 am
Forum: Clarifications on Project Euler Problems
Topic: problem 559
Replies: 5
Views: 2674

Re: problem 559

For each, under the first column, I write an 'a' if row 1 column 1 is smaller than row 2 column 1. Similarly under the 2nd column I write an 'a' if row 1 column 2 is smaller than row 2 column 2. I ignore the 3rd column. An ascent occurs when a whole column is smaller than the column to its right. S...
by jaap
Mon Apr 18, 2016 9:04 am
Forum: News, Suggestions, and FAQ
Topic: Errors/Warnings/Bugs
Replies: 577
Views: 166213

Re: Errors/Warnings/Bugs

Here's a small niggle that may be more trouble than it's worth to fix. When following a problem link such as https://projecteuler.net/problem=556 , I sometimes end up at the About PE page instead of the page for that problem. If I then go back and follow the link again, it does work. I think this ha...
by jaap
Sat Mar 19, 2016 6:19 am
Forum: News, Suggestions, and FAQ
Topic: How to post an original picture?
Replies: 1
Views: 1188

Re: How to post an original picture?

The image needs to be uploaded to a website so the you can access the image with a URL.
The you type the url between [img] and [/img] tags, for example
[img]http://projecteuler.net/images/pe_banner.png[/img].
by jaap
Mon Mar 14, 2016 2:49 pm
Forum: News, Suggestions, and FAQ
Topic: Errors/Warnings/Bugs
Replies: 577
Views: 166213

Re: Errors/Warnings/Bugs

In the forum for problem 333, my first post (second post on the first page) uses the strike-through mark-up codes [s] and [/s]. For some reason the [s] gets turned into [s=] and so no longer displays as strike-through. I'm pretty sure it used to work, but I don't see [s] listed on the [url=https://p...
by jaap
Sun Mar 13, 2016 11:01 am
Forum: News, Suggestions, and FAQ
Topic: Distressed, my big game hunter award taken away
Replies: 4
Views: 2585

Re: Distressed, my big game hunter award taken away

To get the award back you're going to have to sort the problem pages on difficulty and solve at least one more problem on the first two pages. Shouldn't that be "on the first page"? There are 50 problems per page when I look at the archives. A lot of problems have the same difficulty. It seems that...
by jaap
Wed Mar 09, 2016 2:53 pm
Forum: News, Suggestions, and FAQ
Topic: Upset about statement on PE
Replies: 5
Views: 2351

Re: Upset about statement on PE

That is a fair point.
It should be noted however that this message only shows if you are not logged in, but still, simply assuming that people who are not logged in must be new does seem a little rash.