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k a April Highlights and 2025 AoPS Online Class Information
jlacosta   0
Apr 2, 2025
Spring is in full swing and summer is right around the corner, what are your plans? At AoPS Online our schedule has new classes starting now through July, so be sure to keep your skills sharp and be prepared for the Fall school year! Check out the schedule of upcoming classes below.

WOOT early bird pricing is in effect, don’t miss out! If you took MathWOOT Level 2 last year, no worries, it is all new problems this year! Our Worldwide Online Olympiad Training program is for high school level competitors. AoPS designed these courses to help our top students get the deep focus they need to succeed in their specific competition goals. Check out the details at this link for all our WOOT programs in math, computer science, chemistry, and physics.

Looking for summer camps in math and language arts? Be sure to check out the video-based summer camps offered at the Virtual Campus that are 2- to 4-weeks in duration. 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 events:
[list][*]April 3rd (Webinar), 4pm PT/7:00pm ET, Learning with AoPS: Perspectives from a Parent, Math Camp Instructor, and University Professor
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April 9th (Webinar), 4:00pm PT/7:00pm ET, Learn about Video-based Summer Camps at the Virtual Campus
[*]April 10th (Math Jam), 4:30pm PT/7:30pm ET, 2025 MathILy and MathILy-Er Math Jam: Multibackwards Numbers
[*]April 22nd (Webinar), 4:00pm PT/7:00pm ET, Competitive Programming at AoPS (USACO).[/list]
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0 replies
jlacosta
Apr 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
Equations
Jackson0423   1
N 2 minutes ago by Maxklark
Solve the system of equations
\[
\begin{cases}
x - y z = 1,\\[2pt]
y - z x = 2,\\[2pt]
z - x y = 4.
\end{cases}
\]
1 reply
Jackson0423
2 hours ago
Maxklark
2 minutes ago
Calculate the distance of chess king!!
egxa   3
N 5 minutes ago by egxa
Source: All Russian 2025 9.4
A chess king was placed on a square of an \(8 \times 8\) board and made $64$ moves so that it visited all squares and returned to the starting square. At every moment, the distance from the center of the square the king was on to the center of the board was calculated. A move is called $\emph{pleasant}$ if this distance becomes smaller after the move. Find the maximum possible number of pleasant moves. (The chess king moves to a square adjacent either by side or by corner.)
3 replies
+1 w
egxa
Apr 18, 2025
egxa
5 minutes ago
real+ FE
pomodor_ap   4
N 7 minutes ago by jasperE3
Source: Own, PDC001-P7
Let $f : \mathbb{R}^+ \to \mathbb{R}^+$ be a function such that
$$f(x)f(x^2 + y f(y)) = f(x)f(y^2) + x^3$$for all $x, y \in \mathbb{R}^+$. Determine all such functions $f$.
4 replies
pomodor_ap
Yesterday at 11:24 AM
jasperE3
7 minutes ago
FE solution too simple?
Yiyj1   8
N 15 minutes ago by lksb
Source: 101 Algebra Problems from the AMSP
Find all functions $f: \mathbb{R} \rightarrow \mathbb{R}$ such that the equality $$f(f(x)+y) = f(x^2-y)+4f(x)y$$holds for all pairs of real numbers $(x,y)$.

My solution

I feel like my solution is too simple. Is there something I did wrong or something I missed?
8 replies
Yiyj1
Apr 9, 2025
lksb
15 minutes ago
Polynomials in Z[x]
BartSimpsons   16
N 25 minutes ago by bin_sherlo
Source: European Mathematical Cup 2017 Problem 4
Find all polynomials $P$ with integer coefficients such that $P (0)\ne  0$ and $$P^n(m)\cdot P^m(n)$$is a square of an integer for all nonnegative integers $n, m$.

Remark: For a nonnegative integer $k$ and an integer $n$, $P^k(n)$ is defined as follows: $P^k(n) = n$ if $k = 0$ and $P^k(n)=P(P(^{k-1}(n))$ if $k >0$.

Proposed by Adrian Beker.
16 replies
BartSimpsons
Dec 27, 2017
bin_sherlo
25 minutes ago
Why is the old one deleted?
EeEeRUT   13
N 41 minutes ago by EVKV
Source: EGMO 2025 P1
For a positive integer $N$, let $c_1 < c_2 < \cdots < c_m$ be all positive integers smaller than $N$ that are coprime to $N$. Find all $N \geqslant 3$ such that $$\gcd( N, c_i + c_{i+1}) \neq 1$$for all $1 \leqslant i \leqslant m-1$

Here $\gcd(a, b)$ is the largest positive integer that divides both $a$ and $b$. Integers $a$ and $b$ are coprime if $\gcd(a, b) = 1$.

Proposed by Paulius Aleknavičius, Lithuania
13 replies
EeEeRUT
Apr 16, 2025
EVKV
41 minutes ago
Checking a summand property for integers sufficiently large.
DinDean   0
an hour ago
For any fixed integer $m\geqslant 2$, prove that there exists a positive integer $f(m)$, such that for any integer $n\geqslant f(m)$, $n$ can be expressed by a sum of positive integers $a_i$'s as
\[n=a_1+a_2+\dots+a_m,\]where $a_1\mid a_2$, $a_2\mid a_3$, $\dots$, $a_{m-1}\mid a_m$.
0 replies
DinDean
an hour ago
0 replies
Factor sums of integers
Aopamy   2
N an hour ago by cadaeibf
Let $n$ be a positive integer. A positive integer $k$ is called a benefactor of $n$ if the positive divisors of $k$ can be partitioned into two sets $A$ and $B$ such that $n$ is equal to the sum of elements in $A$ minus the sum of the elements in $B$. Note that $A$ or $B$ could be empty, and that the sum of the elements of the empty set is $0$.

For example, $15$ is a benefactor of $18$ because $1+5+15-3=18$.

Show that every positive integer $n$ has at least $2023$ benefactors.
2 replies
Aopamy
Feb 23, 2023
cadaeibf
an hour ago
Least integer T_m such that m divides gauss sum
Al3jandro0000   33
N an hour ago by NerdyNashville
Source: 2020 Iberoamerican P2
Let $T_n$ denotes the least natural such that
$$n\mid 1+2+3+\cdots +T_n=\sum_{i=1}^{T_n} i$$Find all naturals $m$ such that $m\ge T_m$.

Proposed by Nicolás De la Hoz
33 replies
Al3jandro0000
Nov 17, 2020
NerdyNashville
an hour ago
Estonian Math Competitions 2005/2006
STARS   2
N an hour ago by jasperE3
Source: Juniors Problem 4
A $ 9 \times 9$ square is divided into unit squares. Is it possible to fill each unit square with a number $ 1, 2,..., 9$ in such a way that, whenever one places the tile so that it fully covers nine unit squares, the tile will cover nine different numbers?
2 replies
STARS
Jul 30, 2008
jasperE3
an hour ago
Sum of whose elements is divisible by p
nntrkien   43
N an hour ago by lpieleanu
Source: IMO 1995, Problem 6, Day 2, IMO Shortlist 1995, N6
Let $ p$ be an odd prime number. How many $ p$-element subsets $ A$ of $ \{1,2,\dots,2p\}$ are there, the sum of whose elements is divisible by $ p$?
43 replies
nntrkien
Aug 8, 2004
lpieleanu
an hour ago
Arrangement of integers in a row with gcd
egxa   2
N 2 hours ago by Qing-Cloud
Source: All Russian 2025 10.5 and 11.5
Let \( n \) be a natural number. The numbers \( 1, 2, \ldots, n \) are written in a row in some order. For each pair of adjacent numbers, their greatest common divisor (GCD) is calculated and written on a sheet. What is the maximum possible number of distinct values among the \( n - 1 \) GCDs obtained?
2 replies
egxa
Apr 18, 2025
Qing-Cloud
2 hours ago
Integer representation
RL_parkgong_0106   1
N 2 hours ago by Jackson0423
Source: Own
Show that for any positive integer $n$, there exists some positive integer $k$ that makes the following equation have no integer root $(x_1, x_2, x_3, \dots, x_n)$.

$$x_1^{2^1}+x_2^{2^2}+x_3^{2^3}+\dots+x_n^{2^n}=k$$
1 reply
RL_parkgong_0106
4 hours ago
Jackson0423
2 hours ago
Factor of P(x)
Brut3Forc3   19
N 2 hours ago by xytunghoanh
Source: 1976 USAMO Problem 5
If $ P(x),Q(x),R(x)$, and $ S(x)$ are all polynomials such that \[ P(x^5)+xQ(x^5)+x^2R(x^5)=(x^4+x^3+x^2+x+1)S(x),\] prove that $ x-1$ is a factor of $ P(x)$.
19 replies
Brut3Forc3
Apr 4, 2010
xytunghoanh
2 hours ago
Zero tolerance
G H J
G H BBookmark kLocked kLocked NReply
Source: Use your common sense! (enough is enough)
The post below has been deleted. Click to close.
This post has been deleted. Click here to see post.
ZetaX
7579 posts
#1 • 314 Y
Y by yrushi, Binomial-theorem, Mualpha7, amatysten, MiMi1376, Mathematicalx, shinny98NT, RadioActive, Pengu2005, Amir Hossein, Ankoganit, Wizard_32, adityaguharoy, jishu2003, Ultroid999OCPN, Supercali, k2005, abk2015, thecoolchicken, Axle, Ancy, MathCube1717, slhrnds, Rhiju, targo___, Snakes, niyu, someone8888-2, foxtrot3, JRBY, Aniv, samuel, GeronimoStilton, AlPhAtEx, Superguy, heron, Aspirant-to-IMO, Sarbajit10598, chem123, lkarhat, OliverA, integrated_JRC, nckim, PhysicsMonster_01, Bobbyakamurphy, DoingWhatCounts, AnArtist, fry8, microsoft_office_word, cowcow, MathPassionForever, hashtagmath, alex_g, speulers_theorem, GeneralCobra19, yangliardi, mathleticguyyy, mathdragon2000, Bill9000, Carpemath, usernameyourself, AlastorMoody, MathematicalUnicorn, vsamc, jjmath123, solver1104, BobsonJoe, HolyMath, Euler1728, JustKeepRunning, Toinfinity, Karsa, vedonidesimath, Combi1234, limopanda, RishiNandha_M, teomihai, electrovector, OlympiadIneqByBruteForce, middletonkids, amar_04, funmaths, kartik.v, aa1024, ooozeqes, sotpidot, MarkBcc168, StickyWashington, ghu2024, RC., TheCoolDinosuar, eflower2000, mathNart, gamerrk1004, Zorger74, LJCoder619, WizardMath, Purple_Planet, Aspiring_Mathletes, herbs_li, Atpar, Mathsolver19, CaptainLevi16, leibnitz, Kgxtixigct, tree_3, FatherOfIngenuity, geometry6, Mathelogical, CoolCarsOnTheRun, Aryan-23, mg60, b137740, magicarrow, NamePending, fjm30, Pi-rate, ApraTrip, hdrcure, OlympusHero, Rg230403, Euler01, super.shamik, Eliot, FencerRD, happyhippos, nomomon, LightningGirl, Supernova283, Joe__2020, poplintos, lc426, ihatemath123, Abidabi, mobro, Siddharth03, MathJams, ProblemSolver2048, centslordm, amazingxin777, v4913, pog, superagh, winterrain01, cryptographer, rg_ryse, etvat, chrono223, tenebrine, Jc426, hienprogamin1, MERC12345, HamstPan38825, vincentwant, VKU427, aops-g5-gethsemanea2, oVlad, lanadelmath, samrocksnature, Possible, son7, fuzimiao2013, FaThEr-SqUiRrEl, rayfish, Testking, eagles2018, Fordingle, ike.chen, jingwei325, suvamkonar, donotoven, Adventure10, megarnie, captainnobody, brickmaster8, jhu08, Robomania_534, Quidditch, andyloo666, bluelinfish, yjian, Sprites, hh99754539, nikolasxen, HWenslawski, IMUKAT, Flying-Man, Eat314, mod_x, asdf334, Bradygho, boing123, the_mathmagician, qwertyboyfromalotoftime, Han-Ji-Seung, pipitchaya.s4869, Sehraskar, Namodhar1908, polynomialian, RedFlame2112, arcsin2, Pranav1056, asimov, Lasitha_Jayasinghe, Mogmog8, ChromeRaptor777, rama1728, ImSh95, MathLion11, challengeitmath, lgkarras, linda197883, nihao4112, NTfish, NegativeZeroPlusOne, ehz2701, math_comb01, Ansh2020, discretemathcombinatorics, David-Vieta, sehgalsh, hrqdcj, evanhliu2009, Lamboreghini, TheMathCruncher_007, fishgirl, Aopamy, glroavpeh, adorefunctionalequation, nj100, EpicBird08, OronSH, math_sp, Flint_Steel, YOUsername, BDRSDG, GiantSlow, ultimate_life_form, dgkim, aidan0626, jeremy0519, Rainmaker2627, feliciaxu, sl_hc, jf123456, nguyenducmanh2705, Anchovy, IraeVid13, Mango247, Blue_banana4, ESAOPS, Sedro, lpieleanu, fura3334, Stormlight, DU4532, rty, J55406, eg4334, WiseTigerJ1, Exponent11, Yrock, m64sky, Mufara07, mathlover01347, Hello_Kitty, cannotbe, PrateekAtPrime, HoshimiyaMukuro, Kawhi2, pingpongmerrily, Yiyj1, Neilmarar2022, QueenArwen, booking, cubres, whwlqkd, JustAMathFan1, skymagic, quasar_lord, not_using_your_real_name_, avyaank, and 32 other users
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
+"first keyword" +"second keyword"

so that any post containing both strings "first word" and "second form".


c) Good problem statement:
Some recent really bad post was:
Quote:
$lim_{n\to 1}^{+\infty}\frac{1}{n}-lnn$
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.
This post has been edited 3 times. Last edited by jwelsh, Apr 1, 2020, 3:12 PM
Z Y
The post below has been deleted. Click to close.
This post has been deleted. Click here to see post.
Tiks
1144 posts
#2 • 59 Y
Y by adityaguharoy, foxtrot3, Aspirant-to-IMO, electrovector, led, hashtagmath, mathleticguyyy, Carpemath, OliverA, MathGenius_, Vasu090, RishiNandha_M, mathNart, Purple_Planet, theallpro1, franzliszt, OlympusHero, amazingxin777, pog, HamstPan38825, ChromeRaptor777, samrocksnature, judgefan99, suvamkonar, Adventure10, megarnie, jhu08, Quidditch, yjian, Eat314, Bradygho, MathLion11, mathking999, ImSh95, truehoward, nj100, ultimate_life_form, roribaki, EpicBird08, aidan0626, rirobaki, IraeVid13, Reakniseb, Mango247, ESAOPS, WilliamA, cubres, Lhaj3, JustAMathFan1, skymagic, NicoN9, Yiyj1, and 7 other users
Huhhh... :roll: , ZetaX, I see you realy got angree :ninja:. Anyway, I can understand you; It is realy difficult to moderate a forum where there are,hmm...,27567 users :blush: .

I am in 100% agreement with you and I share your points. I think you should have done this long before(but better later than never :) ) and it is adviced to other moderators to undertake this kind of actions in other
sections too.

Thank you!
Z Y
The post below has been deleted. Click to close.
This post has been deleted. Click here to see post.
10000th User
3049 posts
#3 • 42 Y
Y by integrated_JRC, mathleticguyyy, mathdragon2000, Carpemath, Awesome555, kartik.v, mathNart, Purple_Planet, NamePending, OlympusHero, amazingxin777, pog, HamstPan38825, ChromeRaptor777, samrocksnature, centslordm, suvamkonar, jhu08, megarnie, yjian, Bradygho, mathking999, FateGrandOrder, ImSh95, MathLion11, the_mathmagician, ca981, sabkx, ultimate_life_form, Harote, aidan0626, IraeVid13, Adventure10, ESAOPS, kiyoras_2001, cubres, and 6 other users
Kudos to ZetaX. These guidelines, and many more, should have been enforced a long time ago and not just here in NT forum, but ALL other forums ought to follow as well (except maybe G&FF and Test forums). Common sense can be difficult to be defined for certain 'individuals' as they have 'common sense' defined differently.

Some BAD habits seen in some posts that resembles to the ones below:

No self-control: I must post something!!! I must reply! I'm very talkative!

Gibberish: "Yes I solved it hahaha!" "This problem is so easy that it is only for donkeys :roll: :P "

Expressing own feelings that no one really cares: "I got it right and my friends didn't" "What tha heck I didn't get perfect score in AMC!"

Useless answer replies: "is it 420?"

Faulty/no LaTeX used: $cosx=\frac1$

Abundant use of chat/1337 speak: lol omg wtf |-|4><0r5

Repetitive solutions: someone solved the problem and I am posting my solution too, I don't care if it's the same!

Lack of use of hide tags: *scratches head* I dunno how to use 'hide' (dunno=don't know)

And much much more annoying and stupid things I have seen in AoPS/ML.
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ZetaX
7579 posts
#4 • 27 Y
Y by Carpemath, mathNart, Purple_Planet, rf20008, pog, samrocksnature, son7, suvamkonar, Adventure10, megarnie, jhu08, Scooby07, yjian, Bradygho, ImSh95, Mango247, ESAOPS, Kawhi2, cubres, Yiyj1, and 7 other users
I added that contest names aren't good either as titles.
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SpongeBob
188 posts
#5 • 16 Y
Y by mathNart, Purple_Planet, baenanabread, pog, samrocksnature, suvamkonar, Adventure10, megarnie, jhu08, yjian, ImSh95, Mango247, ESAOPS, cubres, axsolers_24, and 1 other user
I always wanted to ask this, and I don't know why I have waited so long... How to use search function????
You can't type latex code if you want to search for some expresion, and if you are looking for same problem in 90% cases, text, beside expresion codes, are useles. Is there some way for using this for which I don't know, because, I get very upset when I see locked post, and message use search function, but I can't find problem like that.

For example this: http://www.mathlinks.ro/Forum/viewtopic.php?p=741742#741742

Can you show how to find this problem.
Tnx

Bye

P.S. If this is not the place for this kind of message, pls delete it, or I will, but pls, answer it...

EDIT: I am sorry I didn't mention this at first, I also support this kind of mesurements for making people to use their common sense, this should be used in other forums too, I can't put up with titles like "hard", and all that in sake of mora functional search function :)
This post has been edited 2 times. Last edited by SpongeBob, Mar 11, 2007, 11:15 PM
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mathmanman
1444 posts
#6 • 9 Y
Y by pog, samrocksnature, Adventure10, megarnie, jhu08, yjian, ImSh95, Mango247, cubres
The keywords "phi positive integers" allow to find it quite quickly, restricting the search to the Number Theory subforum.

Also, I just wanted to say that I strongly agree with ZetaX's decision.
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Hawk Tiger
667 posts
#7 • 9 Y
Y by pog, samrocksnature, megarnie, jhu08, yjian, ImSh95, sabkx, Adventure10, cubres
I agree with you ,ZetaX.But sometimes I don't have many words to show my YOUR COMMON SENSE ,because my English is not good. :blush:
I'll try to do better.
I also find that The search function seldom works.........
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Altheman
6194 posts
#8 • 25 Y
Y by biomathematics, mathleticguyyy, Purple_Planet, Greenleaf5002, OlympusHero, pog, OliverA, samrocksnature, suvamkonar, Adventure10, megarnie, jhu08, yjian, gauss202, snap7822, ImSh95, arfekete, Dansman2838, cubres, and 6 other users
@10000th User:

I disagree with the idea of no repeat solutions. I post solutions for problems because it is instructive for me to write out the proof and to get commentary from other users.
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darij grinberg
6555 posts
#9 • 25 Y
Y by mathleticguyyy, Carpemath, Greenleaf5002, Purple_Planet, Inconsistent, Zorger74, pog, samrocksnature, suvamkonar, jhu08, yjian, megarnie, snap7822, ImSh95, nj100, Dansman2838, Adventure10, Mango247, cubres, and 6 other users
Altheman wrote:
@10000th User:

I disagree with the idea of no repeat solutions. I post solutions for problems because it is instructive for me to write out the proof and to get commentary from other users.

I think he was referring to the lower fores, where solutions often happen to be merely computations etc. Here in the advanced section, it is always ok to post solutions, even if they happen to be equivalent to solutions already posted (it can always happen that the new post is easier to understand than the older one, and there are other reasons as well). It is also ok to post hints if no solutions were posted. But if someone posted a complete proof of an inequality using Cauchy-Schwarz, then it is not ok anymore to post the one-liner "Cauchy-Schwarz pwns it".

darij
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hinhhoc273
33 posts
#10 • 9 Y
Y by pog, samrocksnature, Adventure10, jhu08, yjian, megarnie, ImSh95, Mango247, cubres
But no ones explain 'what is common sense' ?
Thank you for your ideas. I'll try correct my mistakes.
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Stephen
402 posts
#11 • 10 Y
Y by Gumnaami_1945, pog, samrocksnature, jhu08, yjian, megarnie, ImSh95, Adventure10, Mango247, cubres
hinhhoc273 wrote:
But no ones explain 'what is common sense' ?
Thank you for your ideas. I'll try correct my mistakes.

Your common sense is your natural ability to make good judgements and to behave in a pratical and sensible way.
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Stephen
402 posts
#12 • 9 Y
Y by pog, samrocksnature, jhu08, yjian, megarnie, ImSh95, Adventure10, Mango247, cubres
Zetax, a fully agree with you. I'll be good in this site! :lol:
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aspava
53 posts
#13 • 15 Y
Y by mathleticguyyy, Purple_Planet, pog, samrocksnature, Lcz, jhu08, megarnie, ImSh95, Adventure10, Kawhi2, cubres, and 4 other users
interesting
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mastermindh
40 posts
#14 • 9 Y
Y by pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, Mango247, Kawhi2, cubres
Is this allowed to post a solution which is faulty, or the one who posts is not able to recognize whether his solution is complete or not???
Like those who are new to this IMO LEVEL MATHS?
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darij grinberg
6555 posts
#15 • 11 Y
Y by Amir Hossein, OliverA, Purple_Planet, pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, cubres, and 1 other user
Of course it is allowed. Sometimes we can actually learn from others' mistakes. But you should post the solution in a way that people can understand it and see whether it is right or wrong. This is what this whole topic is about. Unfortunately, many people here tend to answer topics with one-sentence posts like "the problem is easy using modulo arithmetic", and whenever somebody points out to them that such a posting is completely useless, they flame him for not having understood their ingenious one-sentence solution. As ZetaX writes, use your common sense. Nobody requires you to double-check every solution you write, but you should make sure it is readable.
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