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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.

Introductory: Grades 5-10

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0 replies
jlacosta
May 1, 2025
0 replies
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k i Adding contests to the Contest Collections
dcouchman   1
N Apr 5, 2023 by v_Enhance
Want to help AoPS remain a valuable Olympiad resource? Help us add contests to AoPS's Contest Collections.

Find instructions and a list of contests to add here: https://artofproblemsolving.com/community/c40244h1064480_contests_to_add
1 reply
dcouchman
Sep 9, 2019
v_Enhance
Apr 5, 2023
J
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k i Zero tolerance
ZetaX   49
N May 4, 2019 by NoDealsHere
Source: Use your common sense! (enough is enough)
Some users don't want to learn, some other simply ignore advises.
But please follow the following guideline:


To make it short: ALWAYS USE YOUR COMMON SENSE IF POSTING!
If you don't have common sense, don't post.


More specifically:

For new threads:


a) Good, meaningful title:
The title has to say what the problem is about in best way possible.
If that title occured already, it's definitely bad. And contest names aren't good either.
That's in fact a requirement for being able to search old problems.

Examples:
Bad titles:
- "Hard"/"Medium"/"Easy" (if you find it so cool how hard/easy it is, tell it in the post and use a title that tells us the problem)
- "Number Theory" (hey guy, guess why this forum's named that way¿ and is it the only such problem on earth¿)
- "Fibonacci" (there are millions of Fibonacci problems out there, all posted and named the same...)
- "Chinese TST 2003" (does this say anything about the problem¿)
Good titles:
- "On divisors of a³+2b³+4c³-6abc"
- "Number of solutions to x²+y²=6z²"
- "Fibonacci numbers are never squares"


b) Use search function:
Before posting a "new" problem spend at least two, better five, minutes to look if this problem was posted before. If it was, don't repost it. If you have anything important to say on topic, post it in one of the older threads.
If the thread is locked cause of this, use search function.

Update (by Amir Hossein). The best way to search for two keywords in AoPS is to input
[code]+"first keyword" +"second keyword"[/code]
so that any post containing both strings "first word" and "second form".


c) Good problem statement:
Some recent really bad post was:
[quote]$lim_{n\to 1}^{+\infty}\frac{1}{n}-lnn$[/quote]
It contains no question and no answer.
If you do this, too, you are on the best way to get your thread deleted. Write everything clearly, define where your variables come from (and define the "natural" numbers if used). Additionally read your post at least twice before submitting. After you sent it, read it again and use the Edit-Button if necessary to correct errors.


For answers to already existing threads:


d) Of any interest and with content:
Don't post things that are more trivial than completely obvious. For example, if the question is to solve $x^{3}+y^{3}=z^{3}$, do not answer with "$x=y=z=0$ is a solution" only. Either you post any kind of proof or at least something unexpected (like "$x=1337, y=481, z=42$ is the smallest solution). Someone that does not see that $x=y=z=0$ is a solution of the above without your post is completely wrong here, this is an IMO-level forum.
Similar, posting "I have solved this problem" but not posting anything else is not welcome; it even looks that you just want to show off what a genius you are.

e) Well written and checked answers:
Like c) for new threads, check your solutions at least twice for mistakes. And after sending, read it again and use the Edit-Button if necessary to correct errors.



To repeat it: ALWAYS USE YOUR COMMON SENSE IF POSTING!


Everything definitely out of range of common sense will be locked or deleted (exept for new users having less than about 42 posts, they are newbies and need/get some time to learn).

The above rules will be applied from next monday (5. march of 2007).
Feel free to discuss on this here.
49 replies
ZetaX
Feb 27, 2007
NoDealsHere
May 4, 2019
J
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how 2 play reaper?
JohannIsBach   3
N 20 minutes ago by JohannIsBach
hi srry if this is in the rong place i dont no where else 2 put it how do u play reaper? and is htere a link 2 the game? just wondering
3 replies
JohannIsBach
an hour ago
JohannIsBach
20 minutes ago
J
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Stamina XP decreasing?
Craftybutterfly   10
N 30 minutes ago by mhgelgi
Summary of the problem: Last night when I checked, alcumus said I had 4250 stamina XP which is more than other people. However, when I just checked, it said I only earned 3905 XP. What is wrong?
Page URL: Hall of Fame
Steps to reproduce:
1. Go to hall of fame
2. Scroll to stamina XP earned
Expected behavior: It should still say I earned 4250 XP
Frequency: 100%
Operating system(s): HP Elitebook
Browser(s), including version: Chrome
IMAGE
10 replies
Craftybutterfly
6 hours ago
mhgelgi
30 minutes ago
J
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Alcumus reset
Happycat2   2
N 34 minutes ago by SapphireKitty
Hi! Because you can't reset your alcumus when your in classes can you email sheriff and let them reset it? My class already ended but I think that you have to wait until it completely disappears but I'm signing up for another class so I can't reset it. So can you email sheriff?
2 replies
Happycat2
an hour ago
SapphireKitty
34 minutes ago
J
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Serbian selection contest for the IMO 2025 - P1
OgnjenTesic   2
N an hour ago by MathLuis
Source: Serbian selection contest for the IMO 2025
Let \( p \geq 7 \) be a prime number and \( m \in \mathbb{N} \). Prove that
\[\left| p^m - (p - 2)! \right| > p^2.\]Proposed by Miloš Milićev
2 replies
+1 w
OgnjenTesic
Today at 4:01 PM
MathLuis
an hour ago
J
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JBMO Shortlist 2021 N1
Lukaluce   15
N 2 hours ago by LeYohan
Source: JBMO Shortlist 2021
Find all positive integers $a, b, c$ such that $ab + 1$, $bc + 1$, and $ca + 1$ are all equal to
factorials of some positive integers.

Proposed by Nikola Velov, Macedonia
15 replies
Lukaluce
Jul 2, 2022
LeYohan
2 hours ago
J
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a+b+c+d divides abc+bcd+cda+dab
v_Enhance   51
N 2 hours ago by BossLu99
Source: USA Team Selection Test for IMO 2021, Problem 1
Determine all integers $s \ge 4$ for which there exist positive integers $a$, $b$, $c$, $d$ such that $s = a+b+c+d$ and $s$ divides $abc+abd+acd+bcd$.

Proposed by Ankan Bhattacharya and Michael Ren
51 replies
v_Enhance
Mar 1, 2021
BossLu99
2 hours ago
J
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Introducing myself at AoPS, and what's your magic wand?
asuth_asuth   1258
N 2 hours ago by JohannIsBach
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.
1258 replies
asuth_asuth
Mar 30, 2025
JohannIsBach
2 hours ago
J
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three discs of radius 1 cannot cover entirely a square surface of side 2
parmenides51   1
N 2 hours ago by Blast_S1
Source: 2014 Romania NMO VIII p4
Prove that three discs of radius $1$ cannot cover entirely a square surface of side $2$, but they can cover more than $99.75\%$ of it.
1 reply
parmenides51
Aug 15, 2024
Blast_S1
2 hours ago
J
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Floor sequence
va2010   88
N 3 hours ago by heheman
Source: 2015 ISL N1
Determine all positive integers $M$ such that the sequence $a_0, a_1, a_2, \cdots$ defined by \[ a_0 = M + \frac{1}{2} \qquad \textrm{and} \qquad a_{k+1} = a_k\lfloor a_k \rfloor \quad \textrm{for} \, k = 0, 1, 2, \cdots \]contains at least one integer term.
88 replies
va2010
Jul 7, 2016
heheman
3 hours ago
J
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2025 Caucasus MO Juniors P6
BR1F1SZ   2
N 3 hours ago by IEatProblemsForBreakfast
Source: Caucasus MO
A point $P$ is chosen inside a convex quadrilateral $ABCD$. Could it happen that$$PA = AB, \quad PB = BC, \quad PC = CD \quad \text{and} \quad PD = DA?$$
2 replies
BR1F1SZ
Mar 26, 2025
IEatProblemsForBreakfast
3 hours ago
J
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Interesting functions with iterations over integers
miiirz30   5
N 3 hours ago by OGMATH
Source: 2025 Euler Olympiad, Round 2
For any subset $S \subseteq \mathbb{Z}^+$, a function $f : S \to S$ is called interesting if the following two conditions hold:

1. There is no element $a \in S$ such that $f(a) = a$.
2. For every $a \in S$, we have $f^{f(a) + 1}(a) = a$ (where $f^{k}$ denotes the $k$-th iteration of $f$).

Prove that:
a) There exist infinitely many interesting functions $f : \mathbb{Z}^+ \to \mathbb{Z}^+$.

b) There exist infinitely many positive integers $n$ for which there is no interesting function
$$ f : \{1, 2, \ldots, n\} \to \{1, 2, \ldots, n\}. $$
Proposed by Giorgi Kekenadze, Georgia
5 replies
miiirz30
Today at 11:07 AM
OGMATH
3 hours ago
J
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Inequality with one variable rational functions
liliput   14
N 3 hours ago by IEatProblemsForBreakfast
Source: 2022 Junior Macedonian Mathematical Olympiad P2
Let $a$, $b$ and $c$ be positive real numbers such that $a+b+c=3$. Prove the inequality
$$\frac{a^3}{a^2+1}+\frac{b^3}{b^2+1}+\frac{c^3}{c^2+1} \geq \frac{3}{2}.$$
Proposed by Anastasija Trajanova
14 replies
liliput
Jun 7, 2022
IEatProblemsForBreakfast
3 hours ago
J
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$7^{7^n}+1$ is the product of at least $2n + 3$ primes
N.T.TUAN   46
N 3 hours ago by reni_wee
Source: USAMO 2007
Prove that for every nonnegative integer $n$, the number $7^{7^{n}}+1$ is the product of at least $2n+3$ (not necessarily distinct) primes.
46 replies
N.T.TUAN
Apr 26, 2007
reni_wee
3 hours ago
J
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n x n square and strawberries
pohoatza   19
N 3 hours ago by atdaotlohbh
Source: IMO Shortlist 2006, Combinatorics 4, AIMO 2007, TST 4, P2
A cake has the form of an $ n$ x $ n$ square composed of $ n^{2}$ unit squares. Strawberries lie on some of the unit squares so that each row or column contains exactly one strawberry; call this arrangement $\mathcal{A}$.

Let $\mathcal{B}$ be another such arrangement. Suppose that every grid rectangle with one vertex at the top left corner of the cake contains no fewer strawberries of arrangement $\mathcal{B}$ than of arrangement $\mathcal{A}$. Prove that arrangement $\mathcal{B}$ can be obtained from $ \mathcal{A}$ by performing a number of switches, defined as follows:

A switch consists in selecting a grid rectangle with only two strawberries, situated at its top right corner and bottom left corner, and moving these two strawberries to the other two corners of that rectangle.
19 replies
pohoatza
Jun 28, 2007
atdaotlohbh
3 hours ago
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
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FoeverResentful
22 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
22 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
22 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
22 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
Z Y
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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
Z Y
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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
650 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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