Activity for trichoplax
Type | On... | Excerpt | Status | Date |
---|---|---|---|---|
Edit | Post #293608 |
Post edited: Make wording more explicit |
— | 4 days ago |
Edit | Post #293609 |
Post edited: Explain that the pattern of factorisations are not in general prime factorisations |
— | 4 days ago |
Edit | Post #293609 |
Post edited: Add motivation section |
— | 4 days ago |
Edit | Post #293609 |
Post edited: Make explicit the conclusion that it also holds for M+1 |
— | 4 days ago |
Edit | Post #293609 | Initial revision | — | 5 days ago |
Answer | — |
A: Prime factor pattern in numbers one less than a power of 2 Yes and no. The pattern of $2^{(2^N)}-1$ being the product of numbers one more than a power of $2$ continues without end. This can be demonstrated using induction (see conjecture and proof below). However, not all of these numbers are prime, so the pattern in the prime factors does not continue. It f... (more) |
— | 5 days ago |
Edit | Post #293608 | Initial revision | — | 5 days ago |
Question | — |
Prime factor pattern in numbers one less than a power of 2 The number $4294967295$ has prime factors $3,5,17,257,\text{and }65537$. The number is one less than a power of $2$, and its prime factors are all one more than a power of $2$. This made me wonder if this happens for other numbers that are one less than a power of $2$. $N$ | $2^{N}-1$ | $\text{... (more) |
— | 5 days ago |
Edit | Post #293602 | Initial revision | — | 8 days ago |
Answer | — |
A: Can I post questions and then answer them? For Codidact communities in general, this question has been asked on Meta: Can you post a question just to answer it yourself? There are several answers there, all confirming that this is allowed and encouraged. For Mathematics Codidact in particular, I see no reason that the answer would be diffe... (more) |
— | 8 days ago |
Comment | Post #292671 |
> point of a convex hull
This suggests a point on the exterior surface.
> accepting the new point if it stays inside the convex shape
This suggests a point in the interior volume.
Could you reword to avoid ambiguity? (more) |
— | 6 months ago |
Edit | Post #292178 |
Post edited: Typo |
— | 8 months ago |
Suggested Edit | Post #292178 |
Suggested edit: Typo (more) |
helpful | 8 months ago |
Comment | Post #292067 |
Although it can be surprising when someone first learns that the volume of a cone or pyramid is independent of the shape of the cross section, that seems to be only a step towards understanding the surprising result presented in the question.
The area of the n-gon at the base of the pyramid will b... (more) |
— | 8 months ago |
Edit | Post #291847 |
Post edited: Typo |
— | 9 months ago |
Suggested Edit | Post #291847 |
Suggested edit: Typo (more) |
helpful | 9 months ago |
Suggested Edit | Post #291824 |
Suggested edit: Add tag (more) |
declined | 9 months ago |
Edit | Post #291825 |
Post edited: Add tag |
— | 9 months ago |
Edit | Post #291824 |
Post edited: Typos |
— | 9 months ago |
Suggested Edit | Post #291825 |
Suggested edit: Add tag (more) |
helpful | 9 months ago |
Suggested Edit | Post #291824 |
Suggested edit: Typos (more) |
helpful | 9 months ago |
Comment | Post #291824 |
Note that [the definition of "miffed"](https://en.wiktionary.org/wiki/miffed) can vary in different regions. In many places "miffed" means upset or irritated, so the usage in this question could cause confusion. It might be more widely understood if "made a mistake" were used instead. (more) |
— | 9 months ago |
Edit | Post #291829 |
Post edited: Add examples of how intuition can be misleading |
— | 9 months ago |
Edit | Post #291829 | Initial revision | — | 9 months ago |
Answer | — |
A: How can you forebode that amount of wood in a napkin ring is the same, regardless of the size of the sphere used ? > (a) Guess which ring has more wood in it. The word "guess" shows that this is not necessarily intended to be guessed correctly. The guess is asked for precisely because the result is unintuitive, and surprising to most people. Writing down your guess emphasises the contrast between what you init... (more) |
— | 9 months ago |
Comment | Post #291827 |
I don't know how many students you teach per year, but if only a little over 1 per year makes this mistake, it sounds like the large majority understand correctly. Are you concerned because you consider this proportion to be unexpectedly high, or because you can't relate to making the mistake at all?... (more) |
— | 9 months ago |
Comment | Post #291687 |
No problem. I can parse it all now. Interesting conjecture. I'll be interested to see if someone can prove it either way. (more) |
— | 10 months ago |
Comment | Post #291687 |
I'm having difficulty understanding the second paragraph. If I've understood the intuitive idea behind the question, then I suspect there may be some typos, but I'm not sufficiently confident in my understanding of your intention to suggest a specific edit.
- Should $2^{n-1}$ instead say $2^n-1$?
... (more) |
— | 10 months ago |
Comment | Post #290727 |
There's some background on bringing content from SE in [an answer on Codidact Meta](https://meta.codidact.com/posts/277998/288937#answer-288937) (more) |
— | about 1 year ago |
Comment | Post #289675 |
> It is rude to alter one's post
It is rude to alter the author's intent. The problem is that sometimes the editor does not realise that a small change is in opposition to the author's intent. It is not rude to make small fixes - that is how the site is intended to work. When people edit with good... (more) |
— | over 1 year ago |
Comment | Post #289675 |
> One could argue that change in readability is negligible. If you arrived at this negligibility argument, then your discussion could arrive at less speculative conclusions.
For me personally, it is perfectly readable once you have explained that it means the same thing, but without that explanati... (more) |
— | over 1 year ago |
Comment | Post #289675 |
> First, let me formulate what I implied from your answer: the both notations are mathematically correct.
I did not say that both notations are mathematically correct. I said that there is no best way to write mathematics. Notation is just convention. I was not asking you to use different notation... (more) |
— | over 1 year ago |
Edit | Post #289675 | Initial revision | — | over 1 year ago |
Answer | — |
A: I would like to receive explanations to the edit to my post. Assuming good intent On Codidact it is standard practice for people to edit each other's posts, and it is intended to be positive and collaborative. The guidance for reviewing edits is as follows: > This edit was suggested by another user. Good edits: > - Improve clarity or fix errors like broke... (more) |
— | over 1 year ago |
Comment | Post #289532 |
I'm not aware of any rules against a user having multiple accounts, so I've [asked about it on Meta](https://meta.codidact.com/posts/289565). (more) |
— | over 1 year ago |
Edit | Post #289538 |
Post edited: Typos |
— | over 1 year ago |
Suggested Edit | Post #289538 |
Suggested edit: Typos (more) |
helpful | over 1 year ago |
Edit | Post #289495 |
Post edited: Replace excessively long MathJax title so that it fits on the page |
— | over 1 year ago |
Edit | Post #289496 |
Post edited: Replace excessively long MathJax title so it fits on the page |
— | over 1 year ago |
Suggested Edit | Post #289495 |
Suggested edit: Replace excessively long MathJax title so that it fits on the page (more) |
helpful | over 1 year ago |
Suggested Edit | Post #289496 |
Suggested edit: Replace excessively long MathJax title so it fits on the page (more) |
helpful | over 1 year ago |
Comment | Post #287462 |
Looks like Peter Taylor has now edited that answer to add double back slashes before every dollar sign, which seems to have the intended effect.
Looks like there are still issues with this. The edit history of that answer shows 2 new backslashes per dollar sign, but only 1 of them is marked as an ... (more) |
— | over 1 year ago |
Comment | Post #288820 |
Some (most?) implementations of minesweeper do not allow a mine to be hit on the first square that is uncovered. Internally, this may involve recalculating the mine positions if the first square uncovered happens to be a mine, so the player never knows.
Can we assume that this applies, so the play... (more) |
— | over 1 year ago |
Edit | Post #288285 |
Post edited: Typo |
— | almost 2 years ago |
Suggested Edit | Post #288285 |
Suggested edit: Typo (more) |
helpful | almost 2 years ago |
Edit | Post #288168 |
Post edited: Missing space |
— | almost 2 years ago |
Edit | Post #288169 |
Post edited: Tidying |
— | almost 2 years ago |
Suggested Edit | Post #288169 |
Suggested edit: Tidying (more) |
helpful | almost 2 years ago |
Edit | Post #288174 | Initial revision | — | almost 2 years ago |
Answer | — |
A: Closed-form expression for sum of Modulo Arithmetic Progression Assumed question Placement of parentheses Your final paragraph suggests that you would already know how to evaluate the following expression: $$ \Bigl( \sum{i=1}^{N} (a \cdot i) \Bigr) \bmod{M} $$ I will therefore assume that your question concerns the following expression: $$ \sum{i=1}^{N... (more) |
— | almost 2 years ago |