Skip to content

Nguyễn Trung Tuân

High School Olympiads

Download


[1] Đề thi chọn đội VMO của Hà Nội https://nttuan.org/2020/06/03/hanoi-tst/

—

Update 28/7/2020.

Share this:

  • Email
  • Print
  • Facebook
  • Twitter

Like this:

Like Loading...
Follow Nguyễn Trung Tuân on WordPress.com

Pages

  • About
  • Contact
  • Download
  • LaTeX
  • Quotes
  • Teaching

Recent Comments

Hopf on Các căn bậc hai là độc lập…
Nguyen Trung Tuan on Một số trang về Olympic T…
Vnt.hnue on Một số trang về Olympic T…
Định lí Pick –… on Popoviciu’s theorem
Nguyen Trung Tuan on Một số trang về Olympic T…

Recent Posts

  • IMO 2021
  • Lớp 9 năm học 2021-2022: Một số đề luyện tập
  • Mathematical Olympiads 2021: Problems from Around the World
  • Các căn bậc hai là độc lập nguyên
  • A proof of Fermat’s theorem

Categories

  • College Math
  • Grade 8, 9
  • Mathematical Olympiad
    • Algebra
    • Combinatorics
    • Contests
    • Geometry
    • Number Theory

Archives

Forums

  • AoPS Community

Journals

  • Forum Geometricorum
  • International Journal of Number Theory
  • Journal of Classical Geometry
  • Journal of Combinatorics and Number Theory
  • Journal of Integer Sequences
  • Journal of Number Theory
  • Komal
  • Kvant
  • Mathematical Excalibur

Links

  • Math.ru
  • MathIM
  • Sharygin
  • WolframAlpha

Math Blogs

  • Combinatorics and more
  • Gowers's Blog
  • What’s new

RSS Number Theory Web

  • An error has occurred; the feed is probably down. Try again later.

RSS Gil Kalai

  • Mathematical news to cheer you up August 1, 2021
    1.  Anna Kiesenhofer, a PhD mathematician researching PDEs at Ecole Polytechnique Federale Lausanne (EPFL), won the gold medal in the women’s bicycle road race at the Olympics. Here are two trivia question: a) Which hero of a recent post over … Continue reading →
    Gil Kalai
  • To Cheer You Up in Difficult Times 28: Math On the Beach (Alef’s Corner) July 13, 2021
    Gil Kalai
  • To cheer you up in difficult times 27: A major recent “Lean” proof verification June 30, 2021
    “Lean is a functional programming language that makes it easy to write correct and maintainable code. You can also use Lean as an interactive theorem prover.” (See Lean’s homepage and see here for an introduction to lean.) Kevin Buzzard’s blog … Continue reading →
    Gil Kalai
  • To cheer you up in difficult times 26: Two real-life lectures yesterday at the Technion June 9, 2021
    After 16 months without lecturing to an audience in my same location, I gave yesterday two lectures at the Technion in front of a live audience (and some additional audience in remote locations). The main lecture was in COMSOC 2021, … Continue reading →
    Gil Kalai
  • To Cheer You Up in Difficult times 24: Borodin’s colouring conjecture! May 30, 2021
    An acyclic colouring of a graph is a colouring of its vertices so that the subgraph spanned on union of every two colour classes is acyclic (a forest). Grunbaum conjectured in 1973 that Every planar graph has acyclic colouring with … Continue reading →
    Gil Kalai
  • To cheer you up in difficult times 25: some mathematical news! (Part 2) May 20, 2021
    Topology Quasi-polynomial algorithms for telling if a knot is trivial Marc Lackenby announced a quasi-polynomial time algorithm to decide whether a given knot is the unknot! This is a big breakthrough. This question is known to be both in NP … Continue reading →
    Gil Kalai
  • To cheer you up in difficult times 23: the original hand-written slides of Terry Tao’s 2015 Einstein Lecture in Jerusalem May 14, 2021
    In 2015 Terry Tao gave the Einstein lecture of the Israeli Academy for Science and Humanities. We got hold of the original signed hand-written slides of Terry’s lecture and we are happy to share them with you. The title of … Continue reading →
    Gil Kalai
  • Alef Corner: ICM2022 May 6, 2021
    Alef’s new piece for ICM 2022 will surely cheer you up!
    Gil Kalai
  • The probabilistic proof that 2^400-593 is a prime: a revolutionary new type of mathematical proof, or not a proof at all? April 22, 2021
    Avi Wigderson gave a great CS colloquium talk at HUJI on Monday (a real auditorium talk with an audience of about 200 people). The title of the talk was The Value of Errors in Proofs – a fascinating journey from … Continue reading →
    Gil Kalai
  • With Avi at Suzanna April 21, 2021
    To cheer you up even further a new story that breaks new ground about Avi Wigderson and me (and Laci Lovasz) and a couple more famous Isrealis. For another story about Avi and me see Layish. (I told both stories … Continue reading →
    Gil Kalai

RSS Terence Tao

  • Varieties of general type with many vanishing plurigenera, and optimal sine and sawtooth inequalities July 26, 2021
    Louis Esser, Burt Totaro, Chengxi Wang, and myself have just uploaded to the arXiv our preprint “Varieties of general type with many vanishing plurigenera, and optimal sine and sawtooth inequalities“. This is an interdisciplinary paper that arose because in order to optimize a certain algebraic geometry construction it became necessary to solve a purely anal […]
    Terence Tao
  • The Gowers uniformity norm of order 1+ July 25, 2021
    In the modern theory of higher order Fourier analysis, a key role are played by the Gowers uniformity norms for . For finitely supported functions , one can define the (non-normalised) Gowers norm by the formula where denotes complex conjugation, and then on any discrete interval and any function we can then define the (normalised) […]
    Terence Tao
  • Quantitative bounds for Gowers uniformity of the Mobius and von Mangoldt functions July 6, 2021
    Joni Teräväinen and myself have just uploaded to the arXiv our preprint “Quantitative bounds for Gowers uniformity of the Möbius and von Mangoldt functions“. This paper makes quantitative the Gowers uniformity estimates on the Möbius function and the von Mangoldt function . To discuss the results we first discuss the situation of the Möbius function, […] […]
    Terence Tao
  • Singmaster’s conjecture in the interior of Pascal’s triangle June 8, 2021
    Kaisa Matomäki, Maksym Radziwill, Xuancheng Shao, Joni Teräväinen, and myself have just uploaded to the arXiv our preprint “Singmaster’s conjecture in the interior of Pascal’s triangle“. This paper leverages the theory of exponential sums over primes to make progress on a well known conjecture of Singmaster which asserts that any natural number larger than a […]
    Terence Tao
  • Goursat and Furstenberg-Weiss type lemmas May 8, 2021
    I’m collecting in this blog post a number of simple group-theoretic lemmas, all of the following flavour: if is a subgroup of some product of groups, then one of three things has to happen: ( too small) is contained in some proper subgroup of , or the elements of are constrained to some sort of […]
    Terence Tao
  • Is there a non-analytic function with all differences analytic? May 4, 2021
    I was asked the following interesting question from a bright high school student I am working with, to which I did not immediately know the answer: Question 1 Does there exist a smooth function which is not real analytic, but such that all the differences are real analytic for every ? The hypothesis implies that […]
    Terence Tao
  • Boosting the van der Corput inequality using the tensor power trick February 27, 2021
    In this previous blog post I noted the following easy application of Cauchy-Schwarz: Lemma 1 (Van der Corput inequality) Let be unit vectors in a Hilbert space . Then Proof: The left-hand side may be written as for some unit complex numbers . By Cauchy-Schwarz we have and the claim now follows from the triangle […]
    Terence Tao
  • The inclusion-exclusion principle for commuting projections February 24, 2021
    The (classical) Möbius function is the unique function that obeys the classical Möbius inversion formula: Proposition 1 (Classical Möbius inversion) Let be functions from the natural numbers to an additive group . Then the following two claims are equivalent: (i) for all . (ii) for all . There is a generalisation of this formula to […]
    Terence Tao
  • Job advertisement: Director of UCLA Endowed Olga Radko Math Circle (ORMC) February 13, 2021
    [I am posting this advertisement in my capacity as chair of the Steering Committee for the UCLA Endowed Olga Radko Math Circle – T.] The Department of Mathematics at the University of California, Los Angeles, is inviting applications for the position of an Academic Administrator who will serve as the Director of the UCLA Endowed […]
    Terence Tao
  • 246B, Notes 4: The Riemann zeta function and the prime number theorem February 12, 2021
    Previous set of notes: Notes 3. Next set of notes: 246C Notes 1. One of the great classical triumphs of complex analysis was in providing the first complete proof (by Hadamard and de la Vallée Poussin in 1896) of arguably the most important theorem in analytic number theory, the prime number theorem: Theorem 1 (Prime […]
    Terence Tao

Blog Stats

  • 1,225,955 hits
loading Cancel
Post was not sent - check your email addresses!
Email check failed, please try again
Sorry, your blog cannot share posts by email.
%d bloggers like this: