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k a May Highlights and 2025 AoPS Online Class Information
jlacosta   0
May 1, 2025
May is an exciting month! National MATHCOUNTS is the second week of May in Washington D.C. and our Founder, Richard Rusczyk will be presenting a seminar, Preparing Strong Math Students for College and Careers, on May 11th.

Are you interested in working towards MATHCOUNTS and don’t know where to start? We have you covered! If you have taken Prealgebra, then you are ready for MATHCOUNTS/AMC 8 Basics. Already aiming for State or National MATHCOUNTS and harder AMC 8 problems? Then our MATHCOUNTS/AMC 8 Advanced course is for you.

Summer camps are starting next month at the Virtual Campus in math and language arts that are 2 - to 4 - weeks in duration. Spaces are still available - don’t miss your chance to have an enriching summer experience. There are middle and high school competition math camps as well as Math Beasts camps that review key topics coupled with fun explorations covering areas such as graph theory (Math Beasts Camp 6), cryptography (Math Beasts Camp 7-8), and topology (Math Beasts Camp 8-9)!

Be sure to mark your calendars for the following upcoming events:
[list][*]May 9th, 4:30pm PT/7:30pm ET, Casework 2: Overwhelming Evidence — A Text Adventure, a game where participants will work together to navigate the map, solve puzzles, and win! All are welcome.
[*]May 19th, 4:30pm PT/7:30pm ET, What's Next After Beast Academy?, designed for students finishing Beast Academy and ready for Prealgebra 1.
[*]May 20th, 4:00pm PT/7:00pm ET, Mathcamp 2025 Qualifying Quiz Part 1 Math Jam, Problems 1 to 4, join the Canada/USA Mathcamp staff for this exciting Math Jam, where they discuss solutions to Problems 1 to 4 of the 2025 Mathcamp Qualifying Quiz!
[*]May 21st, 4:00pm PT/7:00pm ET, Mathcamp 2025 Qualifying Quiz Part 2 Math Jam, Problems 5 and 6, Canada/USA Mathcamp staff will discuss solutions to Problems 5 and 6 of the 2025 Mathcamp Qualifying Quiz![/list]
Our full course list for upcoming classes is below:
All classes run 7:30pm-8:45pm ET/4:30pm - 5:45pm PT unless otherwise noted.

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0 replies
jlacosta
May 1, 2025
0 replies
J
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Introducing myself at AoPS, and what's your magic wand?
asuth_asuth   1055
N 27 minutes ago by d.d0nut
Hi!

I'm Andrew Sutherland. I'm the new Chief Product Officer at AoPS. As you may have read, Richard is retiring and Ben Kornell and I are working together to lead the company now. I'm leading all the software and digital stuff at AoPS. I just wanted to say hello and introduce myself! I'm really excited to be part of the special community that is AoPS.

Previously, I founded Quizlet as a 15-year-old high school student. I did Course 6 at MIT and then left to lead Quizlet full-time for a total of 14 years. I took a few years off and now I'm doing AoPS! I wrote more about all that on my blog: https://asuth.com/im-joining-aops

I have a question for all of you. If you could wave a magic wand, and change anything about AoPS, what would it be? All suggestions welcome! Thank you.
1055 replies
asuth_asuth
Mar 30, 2025
d.d0nut
27 minutes ago
J
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Python exit() module decriptions appear as "undefined"
SoaringHigh   16
N 3 hours ago by LostInBali
Summary of the problem: When using exit() (or quit()) in the Python windows on AoPS the "Description" and "To fix" options show up as "undefined"
sample program
Page URL: N/A
Steps to reproduce:
1. Use the AoPS Python module to execute the exit() or quit() functions in a program. (try running the sample program)
Expected behavior: The "Description" and "To fix" sections give a description of SystemExit
Frequency: Always
Operating system(s): Windows 11 Home
Browser(s), including version: Microsoft Edge 130.0.2849.46
Additional information: N/A
16 replies
SoaringHigh
Oct 22, 2024
LostInBali
3 hours ago
J
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What is the limit?
Disjeje   1
N Today at 7:54 AM by Moubinool
Let’s say An=(sin(n))^n
Does An converge if n reaches infinity?
1 reply
Disjeje
Today at 5:45 AM
Moubinool
Today at 7:54 AM
J
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Putnam 2002 B3
ahaanomegas   2
N Today at 7:36 AM by Rohit-2006
Show that for all integers $n>1$, \[ \dfrac {1}{2ne} < \dfrac {1}{e} - \left( 1 - \dfrac {1}{n} \right)^n < \dfrac {1}{ne}. \]
2 replies
ahaanomegas
Mar 12, 2012
Rohit-2006
Today at 7:36 AM
J
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Putnam 2013 B1
Kent Merryfield   13
N Today at 5:38 AM by Rohit-2006
For positive integers $n,$ let the numbers $c(n)$ be determined by the rules $c(1)=1,c(2n)=c(n),$ and $c(2n+1)=(-1)^nc(n).$ Find the value of \[\sum_{n=1}^{2013}c(n)c(n+2).\]
13 replies
Kent Merryfield
Dec 9, 2013
Rohit-2006
Today at 5:38 AM
J
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Can cos(√2 t) be expressed as a polynomial in cost?
tom-nowy   2
N Today at 4:54 AM by wh0nix
Source: Question arising while viewing https://artofproblemsolving.com/community/c51293h3562250
Can $\cos ( \sqrt{2}\, t )$ be expressed as a polynomial in $\cos t$ with real coefficients?
2 replies
tom-nowy
Yesterday at 7:10 AM
wh0nix
Today at 4:54 AM
J
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Rolles theorem
sasu1ke   7
N Yesterday at 7:27 PM by GentlePanda24

Let \( f: \mathbb{R} \to \mathbb{R} \) be a twice differentiable function such that
\[ f(0) = 2, \quad f'(0) = -2, \quad \text{and} \quad f(1) = 1. \]Prove that there exists a point \( \xi \in (0, 1) \) such that
\[ f(\xi) \cdot f'(\xi) + f''(\xi) = 0. \]

7 replies
sasu1ke
May 3, 2025
GentlePanda24
Yesterday at 7:27 PM
J
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k Reply box disappearing
Craftybutterfly   31
N Yesterday at 4:32 PM by jlacosta
For some reason, on my iPhone XR, when I press on the view my posts button, then press on an unlocked topic and scroll down or press go down button, the reply box disappears. I can’t use the proper format right now as I am on phone.
Summary of the problem: the lines above
setps to reproduce:
1. Go to your profile
2. Press on your posts button
3. press an unlocked topic and scroll down
Frequency: 100%
Browser: Chrome latest version
Device: iPhone XR
31 replies
Craftybutterfly
Apr 30, 2025
jlacosta
Yesterday at 4:32 PM
J
H
k Alcumus Rating
awesometriangles   5
N Yesterday at 4:26 PM by jlacosta
My Alcumus rating for CP used to be something like a 90, then I went to do some homework for a class, and when I came back to alcumus, it is now a 40. I don't know what happened and I haven't touched C&P in the last hour or two, and I haven't gotten any wrong in it or anything to majorly decrease my rating. I also checked the topics, and each was either green or blue, like how I left it. Is this just me?

EDIT: My level is still the same too..., and idk if i should add an image, and if i should, what should I screenshot?
5 replies
awesometriangles
May 5, 2025
jlacosta
Yesterday at 4:26 PM
J
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Convergent series with weight becomes divergent
P_Fazioli   7
N Yesterday at 3:07 PM by P_Fazioli
Initially, my problem was : is it true that if we fix $(b_n)$ positive such that $b_n\underset{{n}\longrightarrow{+\infty}}\longrightarrow +\infty$, then there exists $(a_n)$ positive such that $\displaystyle\sum_{n\geq 0}a_n$ converges and $\displaystyle\sum_{n\geq 0}a_nb_n$ diverges ?

Thinking about the continuous case : if $g:\mathbb{R}_+\longrightarrow\mathbb{R}$ is continuous, positive with $g(x)\underset{{x}\longrightarrow{+\infty}}\longrightarrow +\infty$, does $f$ continuous and positive exist on $\mathbb{R}_+$ such that $\displaystyle\int_0^{+\infty}f(x)\text{d}x$ converges and $\displaystyle\int_0^{+\infty}f(x)g(x)\text{d}x$ diverges ?

To the last question, the answer seems to be yes if $g$ is in the $\mathcal{C}^1$ class, increasing : I chose $f=\dfrac{g'}{g^2}$. With this idea, I had the idea to define $a_n=\dfrac{b_{n+1}-b_n}{b_n^2}$ but it is not clear that it is ok, even if $(b_n)$ is increasing.

Now I have some questions !

1) The main problem : is it true that if we fix $(b_n)$ positive such that $b_n\underset{{n}\longrightarrow{+\infty}}\longrightarrow +\infty$, then there exists $(a_n)$ positive such that $\displaystyle\sum_{n\geq 0}a_n$ converges and $\displaystyle\sum_{n\geq 0}a_nb_n$ diverges ? And if $(b_n)$ is increasing ?
2) is it true that if we fix $(b_n)$ positive increasing such that $b_n\underset{{n}\longrightarrow{+\infty}}\longrightarrow +\infty$
and $\frac{b_{n+1}}{b_n}\underset{{n}\longrightarrow{+\infty}}\longrightarrow 1$, then $\displaystyle\sum_{n\geq 0}\left(\frac{b_{n+1}}{b_n}-1\right)$ diverges ?
3) is it true that if we fix $(b_n)$ positive increasing such that $b_n\underset{{n}\longrightarrow{+\infty}}\longrightarrow +\infty$
and $\frac{b_{n+1}}{b_n}\underset{{n}\longrightarrow{+\infty}}\longrightarrow 1$, then $\displaystyle\sum_{n\geq 0}\frac{b_{n+1}-b_n}{b_n^2}$ converges ?
4) if $(b_n)$ is positive increasing and such that $b_n\underset{{n}\longrightarrow{+\infty}}\longrightarrow +\infty$
and $\frac{b_{n+1}}{b_n}$ does not converge to $1$, can $\displaystyle\sum_{n\geq 0}\frac{b_{n+1}-b_n}{b_n^2}$ diverge ?
5) for the continuous case, is it true if we suppose $g$ only to be continuous ?

7 replies
P_Fazioli
May 5, 2025
P_Fazioli
Yesterday at 3:07 PM
J
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Cool Integral, Cooler Solution
Existing_Human1   2
N Yesterday at 11:33 AM by ysharifi
Source: https://youtu.be/YO38MCdj-GM?si=DCn6DaQTeX8RXhl0
$$\int_{0}^{\infty} \! e^{-x^2}\cos(5x) \,dx$$
Bonus points if you can do it without Feynman
2 replies
Existing_Human1
Yesterday at 2:15 AM
ysharifi
Yesterday at 11:33 AM
J
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Putnam 2016 A1
Kent Merryfield   15
N Yesterday at 10:51 AM by anudeep
Find the smallest positive integer $j$ such that for every polynomial $p(x)$ with integer coefficients and for every integer $k,$ the integer
\[p^{(j)}(k)=\left. \frac{d^j}{dx^j}p(x) \right|_{x=k}\](the $j$-th derivative of $p(x)$ at $k$) is divisible by $2016.$
15 replies
Kent Merryfield
Dec 4, 2016
anudeep
Yesterday at 10:51 AM
J
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Determinant problem
Entrepreneur   2
N Yesterday at 8:27 AM by Entrepreneur
Source: Hall & Knight
If a determinant is of $n^{\text{th}}$ order, and if the constituents of its first, second, ..., $n^{\text{th}}$ rows are the first $n$ figurate numbers of the first, second, ..., $n^{\text{th}}$ orders respectively, show that it's value is $1.$
2 replies
Entrepreneur
May 5, 2025
Entrepreneur
Yesterday at 8:27 AM
J
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36x⁴ + 12x² - 36x + 13 > 0
fxandi   2
N Yesterday at 7:14 AM by MeKnowsNothing
Prove that for any real $x \geq 0$ holds inequality $36x^4 + 12x^2 - 36x + 13 > 0.$
2 replies
fxandi
Monday at 10:02 PM
MeKnowsNothing
Yesterday at 7:14 AM
J
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J
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k AOPS WIki infinite loading
FoeverResentful   6
N Apr 14, 2025 by jlacosta
It appears that whenever you try and go to the wiki page, you end up in a very long waiting screen that either times out or just remains their forever.
6 replies
FoeverResentful
Apr 12, 2025
jlacosta
Apr 14, 2025
J
AOPS WIki infinite loading
G H J
Reveal topic tags
AoPSwiki
L
G H BBookmark kLocked kLocked NReply
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FoeverResentful
18 posts
FoeverResentful
#1 h  Apr 12, 2025, 3:13 AM • 2 Y
Y by Rosie_Xu, jkim0656
It appears that whenever you try and go to the wiki page, you end up in a very long waiting screen that either times out or just remains their forever.
Z Y
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FoeverResentful
18 posts
FoeverResentful
#2 h  Apr 12, 2025, 3:14 AM
Y by
When going into resources tabs and clicking wiki
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FoeverResentful
18 posts
FoeverResentful
#3 h  Apr 12, 2025, 3:14 AM
Y by
https://artofproblemsolving.com/wiki/index.php?title=Main_Page
Z Y
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FoeverResentful
18 posts
FoeverResentful
#4 h  Apr 12, 2025, 3:15 AM
Y by
I used iOS on two different devices using both chrome and safari and it happened nearly every time
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Yiyj1
1266 posts
Yiyj1
#5 h  Apr 12, 2025, 3:17 AM
Y by
sounds like the wiki being normal. it for some reason is just rlly laggy
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Filipjack
873 posts
Filipjack
#6 h  Apr 13, 2025, 7:36 PM
Y by
It used to work fine until about a year ago or so. Now everything on AoPS Wiki takes a tremendous amount of time to open, if it does.

Please fix this.
Z Y
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jlacosta
645 posts
jlacosta
#7 h  Apr 14, 2025, 10:28 PM • 1 Y
Y by Irreplaceable
We are aware of this issue and looking into it!
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