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Contests & Programs AMC and other contests, summer programs, etc.
AMC and other contests, summer programs, etc.
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Contests & Programs AMC and other contests, summer programs, etc.
AMC and other contests, summer programs, etc.
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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
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
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
square geometry bisect $\angle ESB$
GorgonMathDota   12
N an hour ago by AshAuktober
Source: BMO SL 2019, G1
Let $ABCD$ be a square of center $O$ and let $M$ be the symmetric of the point $B$ with respect to point $A$. Let $E$ be the intersection of $CM$ and $BD$, and let $S$ be the intersection of $MO$ and $AE$. Show that $SO$ is the angle bisector of $\angle ESB$.
12 replies
GorgonMathDota
Nov 8, 2020
AshAuktober
an hour ago
Number of modular sequences with different residues
PerfectPlayer   1
N an hour ago by Z4ADies
Source: Turkey TST 2025 Day 3 P9
Let \(n\) be a positive integer. For every positive integer $1 \leq k \leq n$ the sequence ${\displaystyle {\{ a_{i}+ki\}}_{i=1}^{n }}$ is defined, where $a_1,a_2, \dots ,a_n$ are integers. Among these \(n\) sequences, for at most how many of them does all the elements of the sequence give different remainders when divided by \(n\)?
1 reply
PerfectPlayer
Today at 4:17 AM
Z4ADies
an hour ago
Lots of Cyclic Quads
Vfire   104
N 2 hours ago by ravengsd
Source: 2018 USAMO #5
In convex cyclic quadrilateral $ABCD$, we know that lines $AC$ and $BD$ intersect at $E$, lines $AB$ and $CD$ intersect at $F$, and lines $BC$ and $DA$ intersect at $G$. Suppose that the circumcircle of $\triangle ABE$ intersects line $CB$ at $B$ and $P$, and the circumcircle of $\triangle ADE$ intersects line $CD$ at $D$ and $Q$, where $C,B,P,G$ and $C,Q,D,F$ are collinear in that order. Prove that if lines $FP$ and $GQ$ intersect at $M$, then $\angle MAC = 90^\circ$.

Proposed by Kada Williams
104 replies
Vfire
Apr 19, 2018
ravengsd
2 hours ago
D1010 : How it is possible ?
Dattier   13
N 2 hours ago by Dattier
Source: les dattes à Dattier
Is it true that$$\forall n \in \mathbb N^*, (24^n \times B \mod A) \mod 2 = 0 $$?

A=1728400904217815186787639216753921417860004366580219212750904
024377969478249664644267971025952530803647043121025959018172048
336953969062151534282052863307398281681465366665810775710867856
720572225880311472925624694183944650261079955759251769111321319
421445397848518597584590900951222557860592579005088853698315463
815905425095325508106272375728975

B=2275643401548081847207782760491442295266487354750527085289354
965376765188468052271190172787064418854789322484305145310707614
546573398182642923893780527037224143380886260467760991228567577
953725945090125797351518670892779468968705801340068681556238850
340398780828104506916965606659768601942798676554332768254089685
307970609932846902
13 replies
Dattier
Mar 10, 2025
Dattier
2 hours ago
Interesting inequality
sqing   1
N 2 hours ago by sqing
Source: Own
Let $ a,b\geq 2  . $ Prove that
$$ (a^2-1)(b^2-1) (1-ab)+\frac{27}{8}a^2b^2\leq 27$$$$ (a^2-1)(b^2-1)(1-a^2b^2 )+\frac{81}{4}a^2b^2     \leq 189$$$$ (a^2-1)(b^2-1)(1-a^2b^2 )+ 162  ab  \leq 513$$$$  (a^2-1)(b^2-1) (1-a^2b^2 )+21 a^2b^2\leq \frac{3219}{16}$$$$ (a^2-1)(b^2-1) (1-ab)+\frac{27}{8}a^2b^2\leq\frac{415+61\sqrt{61}}{18}$$
1 reply
sqing
3 hours ago
sqing
2 hours ago
Minimal Grouping in a Complete Graph
swynca   1
N 2 hours ago by swynca
Source: 2025 Turkey TST P1
In a complete graph with $2025$ vertices, each edge has one of the colors $r_1$, $r_2$, or $r_3$. For each $i = 1,2,3$, if the $2025$ vertices can be divided into $a_i$ groups such that any two vertices connected by an edge of color $r_i$ are in different groups, find the minimum possible value of $a_1 + a_2 + a_3$.
1 reply
swynca
5 hours ago
swynca
2 hours ago
Nice FE as the First Day Finale
swynca   1
N 2 hours ago by swynca
Source: 2025 Turkey TST P3
Find all $f: \mathbb{R} \rightarrow \mathbb{R}$ such that, for all $x,y \in \mathbb{R}-\{0\}$,
$$ f(x) \neq 0 \text{ and } \frac{f(x)}{f(y)} + \frac{f(y)}{f(x)} - f \left( \frac{x}{y}-\frac{y}{x} \right) =2 $$
1 reply
swynca
4 hours ago
swynca
2 hours ago
Cn/lnn bound for S
EthanWYX2009   0
2 hours ago
Source: 2025 March 谜之竞赛-2
Prove that there exists an constant $C,$ such that for all integer $n\ge 2$ and a subset $S$ of $[n],$ satisfy $a\mid\tbinom ab$ for all $a,b\in S,$ $a>b,$ then $|S|\le \frac{Cn}{\ln n}.$

Created by Yuxing Ye
0 replies
1 viewing
EthanWYX2009
2 hours ago
0 replies
Natural function and cubelike expression
sarjinius   2
N 2 hours ago by Kaimiaku
Source: Philippine Mathematical Olympiad 2025 P8
Let $\mathbb{N}$ be the set of positive integers. Find all functions $f : \mathbb{N} \to \mathbb{N}$ such that for all $m, n \in \mathbb{N}$, \[m^2f(m) + n^2f(n) + 3mn(m + n)\]is a perfect cube.
2 replies
sarjinius
Mar 9, 2025
Kaimiaku
2 hours ago
hard problem
Noname23   3
N 3 hours ago by Noname23
problem
3 replies
Noname23
Sunday at 4:57 PM
Noname23
3 hours ago
average FE
KevinYang2.71   78
N 3 hours ago by rhydon516
Source: USAJMO 2024/5
Find all functions $f:\mathbb{R}\rightarrow\mathbb{R}$ that satisfy
\[
f(x^2-y)+2yf(x)=f(f(x))+f(y)
\]for all $x,y\in\mathbb{R}$.

Proposed by Carl Schildkraut
78 replies
KevinYang2.71
Mar 21, 2024
rhydon516
3 hours ago
Roots, bounding and other delusions
anantmudgal09   28
N 3 hours ago by kes0716
Source: INMO 2021 Problem 6
Let $\mathbb{R}[x]$ be the set of all polynomials with real coefficients. Find all functions $f: \mathbb{R}[x] \rightarrow \mathbb{R}[x]$ satisfying the following conditions:

[list]
[*] $f$ maps the zero polynomial to itself,
[*] for any non-zero polynomial $P \in \mathbb{R}[x]$, $\text{deg} \, f(P) \le 1+ \text{deg} \, P$, and
[*] for any two polynomials $P, Q \in \mathbb{R}[x]$, the polynomials $P-f(Q)$ and $Q-f(P)$ have the same set of real roots.
[/list]

Proposed by Anant Mudgal, Sutanay Bhattacharya, Pulkit Sinha
28 replies
anantmudgal09
Mar 7, 2021
kes0716
3 hours ago
Gunn Math Competition
the_math_prodigy   13
N 4 hours ago by the_math_prodigy
Gunn Math Circle is excited to host the fourth annual Gunn Math Competition (GMC)! GMC will take place at Gunn High School in Palo Alto, California on Sunday, March 30th. Gather a team of up to four and compete for over $7,500 in prizes! The contest features three rounds: Individual, Guts, and Team. We welcome participants of all skill levels, with separate Beginner and Advanced divisions for all students.

Registration is free and now open at compete.gunnmathcircle.org. The deadline to sign up is March 27th.

Special Guest Speaker: Po-Shen Loh!!!
We are honored to welcome Po-Shen Loh, a world-renowned mathematician, Carnegie Mellon professor, and former coach of the USA International Math Olympiad team. He will deliver a 30-minute talk to both students and parents, offering deep insights into mathematical thinking and problem-solving in the age of AI!

View competition manual, schedule, prize pool at compete.gunnmathcircle.org . Stay updated by joining our Discord discord.gg/fqcxukv3Dq server. For any questions, reach out at ghsmathcircle@gmail.com or ask in Discord.
13 replies
the_math_prodigy
Mar 8, 2025
the_math_prodigy
4 hours ago
[TEST RELEASED] Mock Geometry Test for College Competitions
Bluesoul   12
N 5 hours ago by Bluesoul
Hi AOPSers,

I have finished writing a mock geometry test for fun and practice for the real college competitions like HMMT/PUMaC/CMIMC... There would be 10 questions and you should finish the test in 60 minutes, the test would be close to the actual test (hopefully). You could sign up under this thread, PM me your answers!. The submission would close on March 31st at 11:59PM PST.

I would create a private discussion forum so everyone could discuss after finishing the test. This is the first mock I've written, please sign up and enjoy geometry!!

~Bluesoul

Leaderboard
12 replies
Bluesoul
Feb 24, 2025
Bluesoul
5 hours ago
[Tests + Stats Released] SFA's 2021 Orange Mathematics Competition (OMC) 10/12
ilovemath04   201
N Aug 19, 2022 by ASnooby
Hello AoPS!

After a successful mock contest with the OMC 8, STEAM For All is excited to announce its first ever


[center]OMC 10/12[/center]

The virtual Orange Mathematics Competition (OMC) 10/12, is a Mock American Mathematics Competition (AMC) 10/12 with questions written by STEAM for All volunteers! Our problem writers and testsolvers consist of a two-time MOPper, a two-time USAJMO qualifier, and plenty of AIME qualifiers.

The mock contest offers two entirely free online math contests, the OMC 10 and the OMC 12. Students may only take one exam, and students in grades 10 and below are eligible for the OMC 10 while students in grades 12 and below are eligible for the OMC 12. It is a wonderful opportunity for students to engage in a practice test with fun, original questions, listen to experienced competitors explain solutions to the most difficult questions on the exam, and finish off with an awards ceremony to recognize some of the top scoring students!

Register at https://www.steamforall.org/omc-10-12. Registration ends on Thursday, January 21st, 2021 at 12 PM PST.

The competition will be held on Saturday, January 23rd, 2021 from 4 - 6:30PM PST. The general schedule will be as follows (note that all times below are in PST):
4:00 - 4:15 PM: Introduction
4:15 - 5:30 PM: OMC 10/12 Competition
5:30 - 6:15 PM: Problem Review Session
6:15 - 6:30 PM: Awards and Closing Ceremony

FAQ

As for sample problems, here are a few problems from our problem writers that came up on previous contests! Feel free to discuss any of them in this thread.
Sample Problems

More Questions? Contact us at info@steamforall.org or ask in this thread!

We hope that you join us for the upcoming tournament!

Test Links:

OMC 10: https://drive.google.com/file/d/1UVlvprEDwY_l9zTGV7VqW_Ymz1FYQ7Uk/view?usp=sharing

OMC 12: https://drive.google.com/file/d/1SVWk3bJUsMUQR9RUQ1P6YBsIXcHS1uYn/view?usp=sharing

Statistics attached.
201 replies
ilovemath04
Jan 12, 2021
ASnooby
Aug 19, 2022
[Tests + Stats Released] SFA's 2021 Orange Mathematics Competition (OMC) 10/12
G H J
G H BBookmark kLocked kLocked NReply
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WarriorKid
4133 posts
#201 • 3 Y
Y by pbj2006, Ha_ha_ha, Randy_Lee
never even heard of that until now
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math31415926535
5617 posts
#204
Y by
On problem 21 of the OMC 10 I don't really understand the solution. In the solution it said thus, our answer is simply $(1+3+...+2^{2020}-1)+(1+3+...+2^{2019}-1)+...+(2^{1}-1). I don't really understand this part, how did they come up with this conclusion?

And also it would be nice if you guys had video solutions to these problems.
Attachments:
This post has been edited 1 time. Last edited by math31415926535, Feb 2, 2021, 6:05 AM
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ilovemath04
70 posts
#205 • 1 Y
Y by SK_pi3145
@above

Essentially what we're doing is doing casework based on the power of $2$ that divides the numerator. Thus, we would group the numbers as follows:

$0$ powers of $2$: $1,3,5, \cdots, 2^{2020}-1$
$1$ power of $2$: $2,6,10,\cdots,2^{2020}-2$
...
$2019$ powers of $2$: $2^{2019}$

Now, you can see that because the denominator has a huge power of $2$, all powers of $2$ in the numerator of any fraction will have canceled out, so only the odd factors matter. So basically, if we ignore all the powers of $2$, it becomes

$0$ powers of $2$: $1,3,5, \cdots, 2^{2020}-1$
$1$ power of $2$: $1,3,5,\cdots,2^{2019}-1$
...
$2019$ powers of $2$: $1$

Now, note that these are all sums of consecutive odd numbers, which we know add up to perfect squares. Thus, our sum just collapses down to $(2^{2019})^2+(2^{2018})^2+\cdots+(2^{0})^2$, from where you can continue with the official solution.

Regarding the second question, unfortunately, we won't be having video solutions.
This post has been edited 1 time. Last edited by ilovemath04, Feb 2, 2021, 8:31 AM
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henryqi
98 posts
#206
Y by
noooooooooooooo i got 75 ughhhhhhhhhhhhhhhhhh
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Facejo
2847 posts
#207
Y by
Where is the answer key?
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artgag33
96 posts
#208
Y by
Facejo wrote:
Where is the answer key?

here: https://c3aeae64-b3d0-473f-8447-b60fd55684ac.filesusr.com/ugd/e6d77e_59cb2dec76a74b6fb7abaa6792063f64.pdf
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Facejo
2847 posts
#209
Y by

FTFY, but thanks
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phamryd000
19 posts
#210 • 1 Y
Y by Lilathebee
I just mocked this and scored a 76.5. How do my chances for qualifying for AIME look for the AMC 12B this year?
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mm999aops
2634 posts
#211
Y by
hm im ngl in a real amc12 the chance would be perhaps 0.1% but I dont know the dif (like how hard OMC is compared to normal AMC12)
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math31415926535
5617 posts
#212
Y by
phamryd000 wrote:
I just mocked this and scored a 76.5. How do my chances for qualifying for AIME look for the AMC 12B this year?

I think its pretty good, as OMC is a lot harder than normal amc 12.
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phamryd000
19 posts
#213 • 1 Y
Y by Lilathebee
mm999aops wrote:
hm im ngl in a real amc12 the chance would be perhaps 0.1% but I dont know the dif (like how hard OMC is compared to normal AMC12)

If you look at the statistics for this particular mock test, they have the AIME cutoff at 78 points but I'm not so sure how that would translate into a real AIME cutoff
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JenniferChenyingNi
2 posts
#214
Y by
Monkey_king1 wrote:
Yeah, a solution document will be provided, we are working on it right now. Scores will be sent out today hopefully!

Where can I access the solution document?
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asdf334
7579 posts
#215
Y by
who else thought stats for this years omc was released
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Overlord123
799 posts
#216
Y by
this test must be extremely hard if moppers, mc nats cdr, and amc 10 dhr people got between 90 and 105 on the amc 10
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ASnooby
99 posts
#217 • 1 Y
Y by Mango247
How do my chances look for AMC 12 later this year with a 78 on the mock 12? got 3 problems wrong.
got 4 wrong because I thought the wording was "on the circle", got 5 wrong because I drew an octagon, and got 7 wrong because I am bad and forgot $x^2$.

edit: also p13 is based off an ARML preparation problem
This post has been edited 1 time. Last edited by ASnooby, Aug 19, 2022, 2:11 AM
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