Search found 62 matches

by sjhillier
Sun Jan 21, 2018 8:17 pm
Forum: Recreational
Topic: Winning Lottery with Prime Number!?
Replies: 7
Views: 1044

Re: Winning Lottery with Prime Number!?

Interesting talk. For fun, some years ago (20ish!) I did a very naive analysis of the UK lottery to try to determine popular numbers. My results were not very strong, but there was certainly some indication of 1-30 being more popular. However, I noticed another trend that might be worth exploring. A...
by sjhillier
Sun Dec 31, 2017 7:17 pm
Forum: News, Suggestions, and FAQ
Topic: Statistics on problems solved so far
Replies: 18
Views: 1248

Re: Statistics on problems solved so far

However, as of today, the count concerning the one 100% problem I have solved so far has disappeared (it was still there yesterday). Could it be that the way non-finalised difficulties are handled may have changed since yesterday? Or perhaps it is a bug? Yesterday, the table reported 18 available p...
by sjhillier
Fri Dec 29, 2017 8:00 pm
Forum: Number
Topic: Prime generation
Replies: 3
Views: 725

Re: Prime generation

What you have got there are 4 of the lucky numbers of Euler. The others are the rather more trivial smaller values. It has indeed been proved that no larger numbers of this type exist, but I suspect the proof is not so easy. A simpler insight into why this should be would be interesting.
by sjhillier
Sat Dec 16, 2017 10:51 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 616
Replies: 16
Views: 1379

Re: Problem 616

v6ph1 wrote:
Sat Dec 16, 2017 8:33 pm
On my reading, there is no creative number, which can generate all integers >1.
If it makes you feel better, I took about two days to convince myself that the answer was not 0. (I did have real work to do at the time too, or I might have been a bit quicker.)
by sjhillier
Fri Dec 15, 2017 10:39 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 287
Replies: 14
Views: 3173

Re: Problem 287

I think you're right that if you were using this as a genuine image encoding scheme, you'd also have to specify the size, which is not contained in the code itself as described here. However, for the purposes of this problem, we do know N, so the problem is completely determined, even if the encodin...
by sjhillier
Sat Dec 09, 2017 2:48 pm
Forum: News, Suggestions, and FAQ
Topic: About correct form of output
Replies: 3
Views: 249

Re: About correct form of output

In those cases I believe 00012345 and 1.23450 would be correct.

I hope I'm not giving away too much (though it does provide a small amount of extra information) to say that whenever possible, we do try to avoid these sorts of circumstances that are likely to lead to answer formatting difficulties.
by sjhillier
Sat Dec 02, 2017 9:54 pm
Forum: News, Suggestions, and FAQ
Topic: Difficulty Rating for New Problems
Replies: 20
Views: 1263

Re: Difficulty Rating for New Problems

philiplu wrote:
Sat Dec 02, 2017 9:34 pm
Hmm, I guess that means Poohsticks Marathon, Problem 589 (View Problem) was supposed to be easy, given the standard posting cadence?
If it makes you feel better, I did assess this one as Medium, but was out-voted. It's one of those that depends on you having mastered a technique from earlier in the problem set.
by sjhillier
Fri Dec 01, 2017 3:10 pm
Forum: News, Suggestions, and FAQ
Topic: Difficulty Rating for New Problems
Replies: 20
Views: 1263

Re: Difficulty Rating for New Problems

Interesting discussion. I would like to suggest 450 as another under-estimate. From it's position in the sequence, it must have been rated Medium, but turned out to be one of the hardest. I have a particular liking of this problem, since it was my first time in the top 100 (three months after its re...
by sjhillier
Sun Nov 05, 2017 11:41 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 041
Replies: 25
Views: 5230

Re: problem 41

ethereal1m wrote:
Tue Aug 08, 2017 4:33 pm
I got

Code: Select all

98765431
from my calculation but it's wrong.
This answer is wrong as an 8 digit pandigital number must consist of the digits 1-8.
by sjhillier
Thu Jun 08, 2017 6:38 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 353
Replies: 10
Views: 3181

Re: Problem 353

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.
by sjhillier
Thu Jun 08, 2017 1:33 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 261
Replies: 26
Views: 5787

Re: Problem 261

Thierry, your post has been edited, and I've sent you a PM.
by sjhillier
Thu Jun 08, 2017 1:13 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 353
Replies: 10
Views: 3181

Re: Problem 353

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.
by sjhillier
Thu May 25, 2017 6:25 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 604
Replies: 3
Views: 1306

Re: Problem 604

dgokman wrote:
Thu May 25, 2017 12:54 am
Can someone confirm if F(28) = ??????
This is far too early for additional test values.
by sjhillier
Tue May 16, 2017 9:50 pm
Forum: News, Suggestions, and FAQ
Topic: Difficulty Ratings
Replies: 28
Views: 6019

Re: Difficulty Ratings

I would love to see a mix of hard and less-hard questions, kind of how it was prior to problem 350. Am I alone here, or are there anyone else who feels the same way? I value any comments to this. Thanks. Thanks for the interesting thoughts, and thanks also to Muthu for understanding some of the con...
by sjhillier
Tue May 09, 2017 9:42 pm
Forum: Programming languages
Topic: C and C++ are different languages
Replies: 2
Views: 1100

Re: C and C++ are different languages

Would it be possible to separate C and C++ in the list of computer languages? I think this has been addressed (probably several times) in the "New Preferred Programming Language Requests" Topic. See, for example, this post . Personally, I don't have a problem with this grouping, C is essentially a ...
by sjhillier
Mon Apr 03, 2017 5:14 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 276
Replies: 31
Views: 6617

Re: Asking for clarification on Problem 276

Do we have to count degenerated triangles like a=1,b=2 and c=3 or not ? No, a degenerate triangle isn't really a triangle, so don't count them. Explicitly, only count triplets with a+b>c. Please do try to find first if a forum already exists for your problem before starting a new topic. A simple se...
by sjhillier
Sun Apr 02, 2017 12:25 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 082
Replies: 15
Views: 5107

Re: Confusing Wording in Problem 82

I am a newbie here, so apologies if this goes in the wrong forum. I moved the question into the Clarifications for Problem 82 forum, as I think it's more appropriate here. It's always a good idea to see if there's a forum dedicated to a problem first before starting a new topic. As for the question...
by sjhillier
Sun Apr 02, 2017 12:17 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 510
Replies: 11
Views: 2212

Re: Problem 510

vamsikal3 wrote:
Sun Apr 02, 2017 11:11 am
Can someone confirm S(225) = ?????.
Yes it does, but I've edited the post to remove all information!
by sjhillier
Thu Mar 30, 2017 12:25 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 098
Replies: 17
Views: 3915

Re: Problem 098

vjcinjr wrote:
Wed Mar 29, 2017 7:43 pm
I assume you can only use single decimal digits when assigning a number to a character. For example, one can not assign the letter 'C' to the number 12. Correct?
Yes, that's right.
by sjhillier
Sun Mar 19, 2017 2:10 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 070
Replies: 24
Views: 5807

Re: Problem 070

skoczian wrote:
Sun Mar 19, 2017 11:32 am
"How about values of n with repeated digits, would they be regarded as correct solutions?
Yes, they are allowed. Just because they can be regarded as 'multiset permutations' doesn't mean they aren't also permutations.