Project Euler Forum

On page one of this thread, Robert Gerbicz says "No, read the wikipedia's article! For this problem, because the answer will be in [1000,10000) the submitted answer should be in the form: abcd.efghij (and use rounding to get the last digit)." On page two of this thread, daniel.is.fischer says "Ten ...

... 3.) Even though I click "Remember Me" when logging in, I get logged out quite quickly and have to enter a captcha again. I can't reproduce it reliably, though... For this item, what is probably happening is that you are connecting from different computers. Project Euler remembers only the last ...

There seems to be an error in the first sentence of the problem. Any positive integer can be written as a product of prime powers: p 1 a 1 × p 2 a 2 × ... × p k a k , where p i are distinct prime integers, a i > 0 and p i < p j if i < j. A positive power of a prime can't equal 1. Tom 1 is the limit...

@mdenhoed Please don't create a new thread for a problem if one already exists.

After the first page the overview PDFs become very scarce... Would it be a good idea to allow solvers to write stuff and submit if (and should one be good enough it can be chosen) ? This is what the private forum for each problem is all about. The private forum allows each solver to describe his or...

v6ph1 wrote:Yes - there is a summation sign missing.

Changed.

Actually, I can see some problems already have this information in the tooltip! However, some older problems don't seem to have the "Completed on" field present. Has there been some data loss in the past that caused this information to be lost? The date a problem was solved was not collected by the...

apovalyaev wrote:...
828*0.9 = 745.2 and 745.2 < 748. Isn't it correct?

748x1.1 = 822.8 < 828
10% larger than the smallest side is not equivalent to 10% smaller than the larger side.

In Problem 563 (Robot Welders), it's stated as an example the following: "... M(3) = 889200 ..." Is it trully correct? Or this example doesn't square with reality? Cause I found that M(3) = 619344 and three variants are 748x828, 759x816 and 782x792 748x828 is not valid because "the long side must n...

mctrafik wrote:...
If, the mountain peaks were on a grid, then their coordinates would be :
9 - (430, 30)
...

I would double check this value if I were you.

The following is the problem: "..." 1-What are the index, lower bound and upper bound of the summation? 2- Maybe p,q and r , on these two conditions are unique, but if not , are they arbitrary? A) Do not create a new topic when one already exist. B) The summation is over all triplets (p, q, r) that...

It is stated that " The target area of 889200 is the smallest area which can be manufactured in three different variants ". This number seems to be compliant with the problem requirements for M(3) and smaller than 889200 : 865800 = 888 x 975 = 900 x 962 = 925 x 936 Could someone explain why it is n...

Can anybody tell me what "but no turning on the spot" means in the statement of problem 208? Does it mean that a path cannot include a series of 5 clockwise circular arcs or a series of 5 anticlockwise circular arcs? It means there are no sharp angle. Direction changes smoothly from one arc to the ...

square1001 wrote:...
Is there any "memory usage is less than (int)*(500,000,000) (=1.86GB)" solution?

Yes.

square1001 wrote:Problem 205

...

In line 1 and 3, this written "Peter", "Peter and Colin".
In line 4, this written "Pyramidal Pete beats Cubic Colin".

Which is correct, Peter or Pete?

Both are correct. Pete is a diminutive form of the name Peter.

Hello, everyone. I solved for $O(n^3)$ solution in $31$ minutes. I checked the thread and I think my solution and uwi's solution is same, but uwi is computed in $86$ seconds. I think 1-minute rule is unfair because computing speed is very different in different PC. What do you think? Please tell me...

To the admins, please read my comment on the forum for Project 8 solutions. This is STILL unclear, and I was able to FINALLY solve it via a whim I had. The problem is POORLY presented and confusing for such a simple solution. Please don't create a new topic when one already exist for a problem. It ...

Hi! Can someone please help me solve this problem in Wolfram Mathematica? I've seen people post solutions using c++, python, java, and so on but none in Mathematica. Mathematica isn't really my cup of tea(to be perfectly honest, I haven't got a clue about it at all) and I really need to do this for...

I have spent a lot of time on this one. Is there some mathematical theorem or concept I need to read first to solve this. Please suggest something to read for this, if there is. This problem is challenging, but it can still be solved using only simple principles already used in dozens of other Proj...

sheepweevil wrote:Are the balls drawn with or without replacement? It's not clear to me from the problem description.

Without replacement.