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Activity for Peter Taylor‭

Type On... Excerpt Status Date
Edit Post #290494 Initial revision 11 months ago
Answer A: Is there a $(n_3)$ configuration which is not self-dual?
OEIS has A001403 Number of combinatorial configurations of type (n3). A100001 Number of self-dual combinatorial configurations of type (n3). They first differ at $n=11$. An example of a non-self-dual configuration of type $(113)$ has points $0$ to $10$ and lines $[0, 1, 2]$, $[0, 3, 4]$, $[0...
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11 months ago
Edit Post #290157 Post edited:
Use conventional placement of binding operators
about 1 year ago
Comment Post #290025 More generally, when $n > m$ the sum has no support so the LHS is zero.
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about 1 year ago
Comment Post #289814 The page you link for tau-distribution says (variables adjusted for consistency with your presentation) "In fact, this implies that $\frac{\tau_\nu^2}{\nu}$ follows the beta distribution $B(\frac12,\frac{ν − 1}2)$." Is that effectively an answer? Stats was never my strongest subject and I'm very rust...
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about 1 year ago
Edit Post #289811 Initial revision about 1 year ago
Answer A: How can I improve contrast of red and green, to prove Reverse Triangle Inequality?
The obvious answer to how to amplify the the difference in length between $|\vec{b}| - |\vec{r}|$ and $|\vec{b} - \vec{r}|$ is to set $r = -b$ so that one difference is zero and the other is arbitrarily large.
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about 1 year ago
Comment Post #289757 I'm not sure why it's relevant that they're 16-year-olds, and that prompts me to consider that this is really a question for teachers about pedagogy rather than for mathematicians about mathematics, so this may not be the right place to ask. I've raised the scope question [on meta](https://math.codid...
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about 1 year ago
Edit Post #289810 Initial revision about 1 year ago
Question Is mathematical pedagogy in scope?
Do we want to consider questions about how to teach mathematics in scope, or do we want to restrict questions to actually doing mathematics?
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about 1 year ago
Comment Post #289760 If you think the previous question needs improving, edit the previous question rather than duplicating it with minor tweaks.
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about 1 year ago
Edit Post #289760 Question closed about 1 year ago
Comment Post #289671 Firstly, it wasn't my edit. I don't understand why you call it my edit after having described the situation accurately in the question. Secondly, I understood the question to be about the edit summary. If that wasn't the main point, I suggest either editing the question or asking a new one. Thirdly, ...
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about 1 year ago
Comment Post #289671 I wanted to approve the edit but change the edit summary to remove the mention of correctness, but this option wasn't available.
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about 1 year ago
Edit Post #289518 Initial revision about 1 year ago
Answer A: Picture proof for expansion of $x^n−y^n$
$$\begin{array}{c} \times & \mid & x^{n−1} & +x^{n−2}y & +\ldots & +xy^{n−2} & +y^{n−1} \\ \hline x & \mid & x^n & {\color{blue} +x^{n−1}y} & +\ldots & +x^2 y^{n−2} & {\color{green} +x y^{n−1}} \\ -y & \mid & {\color{blue} -x^{n−1}y} & -x^{n−2}y^2 & -\ldots & {\color{green} -xy^{n−1}} & -y^n \end...
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about 1 year ago
Edit Post #289435 Initial revision over 1 year ago
Answer A: Classification for involutory real infinite series
If we look at formal power series and ignore questions of convergence for now, we can take $f(x) = \sum{i \ge 0} ai x^i$. Then the question is which sequences of $ai$ satisfy $$\sum{j \ge 0} aj \left(\sum{i \ge 0} ai x^i\right)^j = x$$ The case $a0 \neq 0$ is awkward, because we immediately get th...
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over 1 year ago
Comment Post #289216 What exactly do you mean by "real infinite series"? Without the surrounding context I would interpret it as a function $\mathbb{N} \to \mathbb{R}$, but that can't be involutory unless it's an infinite series of natural numbers, in which case specifying "real" makes no sense. Are you looking for analy...
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over 1 year ago
Comment Post #289012 Maybe someone with more imagination than me can see a way, but I'm not.
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over 1 year ago
Comment Post #289012 The question "But why do most answers on lotteries consider the Pr(winning jackpot in 1 play)" might be on-topic as a *meta* question, but the answer is going to be along the lines of "Because that's what the questions ask about". As to *Homo economicus*, this is a mathematics site, and while tightly...
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over 1 year ago
Edit Post #289012 Question closed over 1 year ago
Edit Post #289007 Post edited:
The escaping interactions between MarkDown and MathJax are pretty nasty. This particular combination of single and double backslashes works in the preview
over 1 year ago
Comment Post #288820 Yes. Consider a 3x3 grid with mines at (0,1), (1,0), (1,1) and an initial clue at (2,2).
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over 1 year ago
Edit Post #288767 Initial revision over 1 year ago
Answer A: Should posting on Meta affect reputation?
It seems like a good thing to reward useful contributions to Meta, but probably not as much as useful contributions to Q&A. I have mixed feelings about negative scores for downvotes, but bearing in mind the use of downvotes to express disagreement with good-faith proposals I'm inclined to remove them...
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over 1 year ago
Comment Post #288729 I assume that the values are integers. What are the default values and the supported bounds?
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over 1 year ago
Comment Post #287787 I think you've missed the "(End)". The paragraph about 49 is part of [Schoenfield's original submission](https://oeis.org/history/view?seq=A309981&v=3).
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over 1 year ago
Edit Post #288114 Post edited:
I've removed the colours in the question, so to avoid confusion I'm removing references to them
over 1 year ago
Edit Post #288113 Post edited:
Remove non-mathematical content and inappropriate use of mathematical markup which reduces the accessibility of the question
over 1 year ago
Comment Post #288113 The first question is borderline mathematical. The second question is not, so I'm going to edit to remove it.
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over 1 year ago
Edit Post #288080 Initial revision over 1 year ago
Answer A: How to intuit P(win the same lottery twice) $= p^{2}$ vs. P(win the same lottery twice | you won the lottery once) $= p$?
> It feels contradictory for P(you win the same lottery twice) $\neq$ P(you win the same lottery twice|you won the lottery once). Would you expect P(you win the lottery exactly zero times) = P(you win the lottery exactly zero times | you won the lottery once)? > Intuitively, why aren't these ...
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over 1 year ago
Edit Post #288039 Post edited:
over 1 year ago
Edit Post #288039 Post edited:
over 1 year ago
Edit Post #288039 Post edited:
over 1 year ago
Edit Post #288039 Post edited:
over 1 year ago
Comment Post #288022 I haven't analysed it in detail, but I don't think that *a priori* it can be assumed to be fallacious.
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over 1 year ago
Comment Post #288022 It's not impossible in principle to make a profit by buying every number combination, although it requires a large syndicate both to invest and to obtain the tickets; a lottery where unwon prizes roll over so that the jackpot gets large enough to be worth it; and a bit of luck so that you're not shar...
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over 1 year ago
Comment Post #287999 I was specifically assuming that the numbers on each ticket are *not* randomly generated but chosen by the player.
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over 1 year ago
Comment Post #287999 I would say that in the context of the question the chance of winning is linear with the number of tickets because we can assume that the tickets will not have the same numbers, and a perfect match with the selected numbers is required to win, so they cover different outcomes of a single event.
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over 1 year ago
Edit Post #287998 Post edited:
It's not necessary to put the entire post in bold; compact the comparable data into one table; the Daily Keno description was insufficient to say anything meaningful
over 1 year ago
Edit Post #287973 Question closed over 1 year ago
Edit Post #287958 Question closed over 1 year ago
Comment Post #287958 To properly answer this question we would need full details on the prize structure (because most lotteries have more than just the top prize) and sufficient details on the ticket structure to estimate the chances of prizes being shared.
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over 1 year ago
Comment Post #287787 Certainly $p_0 \in$ [A183064](https://oeis.org/A183064) shows that candidates are quite sparse.
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almost 2 years ago
Edit Post #287787 Post edited:
Tweak for consistency
almost 2 years ago
Edit Post #287787 Initial revision almost 2 years ago
Question Prove that 49 is the only prime square to be followed by twice a prime square and then a semiprime
Let $\tau(n)$ denote the number of divisors of $n$. OEIS sequence A309981 gives the smallest $k$ such that the tuple $(\tau(n), \tau(n+1), \ldots, \tau(n+k))$ uniquely determines $n$. For small $n$ the value can often be verified by case analysis in residues to a suitable modulus, but $n=49$ is mo...
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almost 2 years ago
Comment Post #287764 I think that it's intended to be seen as community reputation rather than mathematics reputation: it measures your contribution to the math.codidact.com community (and that, in turn, is arguably a proxy for activity in the math.codidact.com community, as long as you're not mainly making posts which g...
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almost 2 years ago