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k a March Highlights and 2025 AoPS Online Class Information
jlacosta   0
Mar 2, 2025
March is the month for State MATHCOUNTS competitions! Kudos to everyone who participated in their local chapter competitions and best of luck to all going to State! Join us on March 11th for a Math Jam devoted to our favorite Chapter competition problems! Are you interested in training for MATHCOUNTS? Be sure to check out our AMC 8/MATHCOUNTS Basics and Advanced courses.

Are you ready to level up with Olympiad training? Registration is open with early bird pricing available for our WOOT programs: MathWOOT (Levels 1 and 2), CodeWOOT, PhysicsWOOT, and ChemWOOT. What is WOOT? WOOT stands for Worldwide Online Olympiad Training and is a 7-month high school math Olympiad preparation and testing program that brings together many of the best students from around the world to learn Olympiad problem solving skills. Classes begin in September!

Do you have plans this summer? There are so many options to fit your schedule and goals whether attending a summer camp or taking online classes, it can be a great break from the routine of the school year. Check out our summer courses at AoPS Online, or if you want a math or language arts class that doesn’t have homework, but is an enriching summer experience, our AoPS Virtual Campus summer camps may be just the ticket! We are expanding our locations for our AoPS Academies across the country with 15 locations so far and new campuses opening in Saratoga CA, Johns Creek GA, and the Upper West Side NY. Check out this page for summer camp information.

Be sure to mark your calendars for the following events:
[list][*]March 5th (Wednesday), 4:30pm PT/7:30pm ET, HCSSiM Math Jam 2025. Amber Verser, Assistant Director of the Hampshire College Summer Studies in Mathematics, will host an information session about HCSSiM, a summer program for high school students.
[*]March 6th (Thursday), 4:00pm PT/7:00pm ET, Free Webinar on Math Competitions from elementary through high school. Join us for an enlightening session that demystifies the world of math competitions and helps you make informed decisions about your contest journey.
[*]March 11th (Tuesday), 4:30pm PT/7:30pm ET, 2025 MATHCOUNTS Chapter Discussion MATH JAM. AoPS instructors will discuss some of their favorite problems from the MATHCOUNTS Chapter Competition. All are welcome!
[*]March 13th (Thursday), 4:00pm PT/7:00pm ET, Free Webinar about Summer Camps at the Virtual Campus. Transform your summer into an unforgettable learning adventure! From elementary through high school, we offer dynamic summer camps featuring topics in mathematics, language arts, and competition preparation - all designed to fit your schedule and ignite your passion for learning.[/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
Mar 2, 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
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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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AMC 12a 2024 Problems and Solutions Pages Misaligned?
ViolinGod   3
N 17 minutes ago by Toinfinity
I was looking at the past AMC problems and it seems like the problems listed on this page:

https://artofproblemsolving.com/wiki/index.php/2024_AMC_12A_Problems

have solution links that do not all correspond to the correct problem. For example, for problem 2, the solution page is linked as:

https://artofproblemsolving.com/wiki/index.php/2024_AMC_12A_Problems/Problem_2, but in the first link the problems are different.
3 replies
ViolinGod
3 hours ago
Toinfinity
17 minutes ago
J
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Function Equation
Dynic   1
N 33 minutes ago by pco
Find all $f:\mathbb{R} \to \mathbb{R}$ such that
$$f(x-f(y))=f(x+f(y)+y^5)+f(2f(y)+y^5)+2025,\forall x,y\in \mathbb{R}$$
1 reply
Dynic
an hour ago
pco
33 minutes ago
J
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Colouring numbers
kitun   2
N an hour ago by quasar_lord
What is the least number required to colour the integers $1, 2,.....,2^{n}-1$ such that for any set of consecutive integers taken from the given set of integers, there will always be a colour colouring exactly one of them? That is, for all integers $i, j$ such that $1<=i<=j<=2^{n}-1$, there will be a colour coloring exactly one integer from the set $i, i+1,.... , j-1, j$.
2 replies
kitun
Nov 15, 2021
quasar_lord
an hour ago
J
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Mathhhhh
mathbetter   4
N an hour ago by Amkan2022
Three turtles are crawling along a straight road heading in the same
direction. "Two other turtles are behind me," says the first turtle. "One turtle is
behind me and one other is ahead," says the second. "Two turtles are ahead of me
and one other is behind," says the third turtle. How can this be possible?
4 replies
mathbetter
Yesterday at 11:21 AM
Amkan2022
an hour ago
J
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Finally hard NT on UKR MO from NT master
mshtand1   3
N an hour ago by Jupiterballs
Source: Ukrainian Mathematical Olympiad 2025. Day 1, Problem 11.4
A pair of positive integer numbers \((a, b)\) is given. It turns out that for every positive integer number \(n\), for which the numbers \((n - a)(n + b)\) and \(n^2 - ab\) are positive, they have the same number of divisors. Is it necessarily true that \(a = b\)?

Proposed by Oleksii Masalitin
3 replies
mshtand1
Mar 13, 2025
Jupiterballs
an hour ago
J
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Sequence bounding itself
juckter   2
N 2 hours ago by Math-Problem-Solving
Source: Own
We say a sequence of integers $a_1, a_2, \dots, a_n$ is self-bounded if for each $i$, $1 \le i \le n$ there exist at least $a_i$ terms of the sequence that are less than or equal to $i$. Find the maximum possible value of $a_1 + a_2 + \dots + a_n$ for a self-bounded sequence $a_1, a_2, \dots, a_n$.
2 replies
juckter
Jan 13, 2021
Math-Problem-Solving
2 hours ago
J
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Checkerboard
Ecrin_eren   0
2 hours ago
On an 8×8 checkerboard, what is the minimum number of squares that must be marked (including the marked ones) so that every square has exactly one marked neighbor? (We define neighbors as squares that share a common edge, and a square is not considered a neighbor of itself.)
0 replies
Ecrin_eren
2 hours ago
0 replies
J
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An inequality
JK1603JK   3
N 3 hours ago by lbh_qys
Source: unknown
Let a,b,c>=0: ab+bc+ca=3 then maximize P=\frac{a^2b+b^2c+c^2a+9}{a+b+c}+\frac{abc}{2}.
3 replies
JK1603JK
Yesterday at 10:28 AM
lbh_qys
3 hours ago
J
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Find (a,n)
shobber   70
N 3 hours ago by cherry265
Source: China TST 2006 (1)
Find all positive integer pairs $(a,n)$ such that $\frac{(a+1)^n-a^n}{n}$ is an integer.
70 replies
shobber
Mar 24, 2006
cherry265
3 hours ago
J
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FE with 2 degrees
Adywastaken   2
N 3 hours ago by Adywastaken
Source: Serbia 2021/5
Find all $f:\mathbb{R}\rightarrow\mathbb{R}$ such that $f(xf(y)+x^2+y)=f(x)f(y)+xf(x)+f(y) \forall x,y \in \mathbb{R}$
2 replies
Adywastaken
Yesterday at 12:29 PM
Adywastaken
3 hours ago
J
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keep one card and discard the other
Scilyse   2
N 3 hours ago by flower417477
Source: CGMO 2024 P2
There are $8$ cards on which the numbers $1$, $2$, $\dots$, $8$ are written respectively. Alice and Bob play the following game: in each turn, Alice gives two cards to Bob, who must keep one card and discard the other. The game proceeds for four turns in total; in the first two turns, Bob cannot keep both of the cards with the larger numbers, and in the last two turns, Bob also cannot keep both of the cards with the larger numbers. Let $S$ be the sum of the numbers written on the cards that Bob keeps. Find the greatest positive integer $N$ for which Bob can guarantee that $S$ is at least $N$.
2 replies
Scilyse
Jan 28, 2025
flower417477
3 hours ago
J
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Number of posts is not consistent
LawofCosine   3
N Today at 1:27 AM by LawofCosine
The number of posts is not consistent. see attachments. Thank you.
3 replies
LawofCosine
Today at 1:16 AM
LawofCosine
Today at 1:27 AM
J
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The avatars are not consistent
Craftybutterfly   24
N Yesterday at 11:47 PM by Demetri
Summary of the problem: The avatars are not consistent
Page URL: idk
Steps to reproduce:
1. change your avatar
2.reload a topic you posted in
3. do #2 to a different topic with your post in it
Expected behavior: Avatars are the same
Frequency: 100%
Operating system(s): MacOS
Browser(s), including version: Chrome latest version
Additional information: refreshing does not help, neither does logging out and in
24 replies
Craftybutterfly
Yesterday at 5:48 AM
Demetri
Yesterday at 11:47 PM
J
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k How to add members to forums?
Bnn81351   2
N Yesterday at 5:22 AM by Craftybutterfly
How do I add members to forums?
2 replies
Bnn81351
Yesterday at 12:55 AM
Craftybutterfly
Yesterday at 5:22 AM
J
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J
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k Somehow I broke the unique contest collection naming...
Equinox8   1
N Mar 14, 2025 by jlacosta
Somehow I broke the unique contest collection naming scheme; for what it's worth, I also ran into an AJAX timeout error while trying to make this particular post collection for the first time, and pressed "create" twice.

Not sure if there's anything to be done here, but are there potentially unforeseen consequences here?

https://artofproblemsolving.com/community/c4258765_2024_puerto_rico_team_selection_test (this is the one I'm working on; it's also not finished yet)
https://artofproblemsolving.com/community/c4258764_2024_puerto_rico_team_selection_test
1 reply
Equinox8
Mar 12, 2025
jlacosta
Mar 14, 2025
J
Somehow I broke the unique contest collection naming...
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Reveal topic tags
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Equinox8
1735 posts
Equinox8
#1 h  Mar 12, 2025, 4:57 PM
Y by
Somehow I broke the unique contest collection naming scheme; for what it's worth, I also ran into an AJAX timeout error while trying to make this particular post collection for the first time, and pressed "create" twice.

Not sure if there's anything to be done here, but are there potentially unforeseen consequences here?

https://artofproblemsolving.com/community/c4258765_2024_puerto_rico_team_selection_test (this is the one I'm working on; it's also not finished yet)
https://artofproblemsolving.com/community/c4258764_2024_puerto_rico_team_selection_test
This post has been edited 2 times. Last edited by Equinox8, Mar 12, 2025, 5:25 PM
Reason: clarity
Z Y
The post below has been deleted. Click to close.
This post has been deleted. Click here to see post.
jlacosta
603 posts
jlacosta
#2 h  Mar 14, 2025, 10:25 PM • 1 Y
Y by Equinox8
Hi Equinox08! The "E_AJAX_TIMEOUT" is a known error message and likely appearing because the request for data timed out. Usually, a hard refresh of the page resolves this issue.

It appears that two forums were created, so we have gone ahead and deleted the second forum.
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