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 Second third of my ICM 2018 paper – Three Puzzles on Mathematics, Computation and Games. Corrections and comments welcome
 First third of my ICM2018 paper – Three Puzzles on Mathematics, Computation and Games. Corrections and comments welcome
 Preview: The solution by Keller and Lifshitz to several open problems in extremal combinatorics
 Basic Notions Seminar is Back! Helly Type Theorems and the Cascade Conjecture
 My Very First Book “Gina Says”, Now Published by “World Scientific”
 Itai Benjamini: Coarse Uniformization and Percolation & A Paper by Itai and me in Honor of Lucio Russo
 AfterDinner Speech for Alex Lubotzky
 Boaz Barak: The different forms of quantum computing skepticism
 Bálint Virág: Random matrices for Russ
Top Posts & Pages
 Second third of my ICM 2018 paper  Three Puzzles on Mathematics, Computation and Games. Corrections and comments welcome
 Believing that the Earth is Round When it Matters
 TYI 30: Expected number of Dice throws
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 If Quantum Computers are not Possible Why are Classical Computers Possible?
 A Breakthrough by Maryna Viazovska Leading to the Long Awaited Solutions for the Densest Packing Problem in Dimensions 8 and 24
 First third of my ICM2018 paper  Three Puzzles on Mathematics, Computation and Games. Corrections and comments welcome
 How the gConjecture Came About
 Eran Nevo: gconjecture part 4, Generalizations and Special Cases
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Category Archives: Test your intuition
Stan Wagon, TYI 23: Ladies and Gentlemen: The Answer
TYI 32, kindly offered by Stan Wagon asked A round cake has icing on the top but not the bottom. Cut out a piece in the usual shape (a sector of a circle with vertex at the center), remove it, … Continue reading
Posted in Combinatorics, Geometry, Test your intuition
Tagged Stan Wagon, Test your intuition
8 Comments
TYI 31 – Rados Radoicic’s Rope Problem
Ropemaker (source) Rados Radoicic wrote me: “Several years back, I heard the following puzzle that turns out to be rather ‘classical’: “There are N ropes in a bag. In each step, two rope ends are picked uniformly at random, tied … Continue reading
Posted in Combinatorics, Probability, Test your intuition
Tagged Rados Radoicic, Test your intuition
7 Comments
Elchanan Mossel’s Amazing Dice Paradox (your answers to TYI 30)
TYI 30 asked Elchanan Mossel’s Amazing Dice Paradox (that I heard from Yuval Peres yesterday) You throw a die until you get 6. What is the expected number of throws (including the throw giving 6) conditioned on the event that all throws … Continue reading
Posted in Combinatorics, Probability, Test your intuition
Tagged condition probability, Elchanan Mossel
62 Comments
TYI 30: Expected number of Dice throws
Test your intuition: You throw a dice until you get 6. What is the expected number of throws (including the throw giving 6) conditioned on the event that all throws gave even numbers. followup post
Test your intuition 29: Diameter of various random trees
Both trees in general and random trees in particular are wonderful objects. And there is nothing more appropriate to celebrate Russ Lyons great birthday conference “Elegance in Probability” (taking place now in Tel Aviv) than to test your intuition, dear … Continue reading
Posted in Combinatorics, Probability, Test your intuition
Tagged Russ Lyons, Test your intuition
19 Comments
Test your intuition 28: What is the most striking common feature to all these remarkable individuals
Test your intuition: What is the most striking common feature to all these fifteen remarkable individuals László Babai; Avi Wigderson; Lance Fortnow; Lane Hemaspaandra; Sampath Kannan; Hal Gabow; Richard Karp; Tom Leighton; Rockford J. Ross; Alan Selman; Michael Langston; S. … Continue reading
Test Your Intuition (27) about the AlonTarsi Conjecture
On the occasion of Polymath 12 devoted to the Rota basis conjecture let me remind you about the AlonTarsi conjecture and test your intuition concerning a strong form of the conjecture. The sign of a Latin square is the product … Continue reading
Posted in Combinatorics, Open problems, Test your intuition
Tagged AlonTarsi conjecture, Polymath12
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TYI 26: Attaining the Maximum
(Thanks, Dani!) Given a random sequence , ******, , let . and assume that . What is the probability that the maximum value of is attained only for a single value of ? Test your intuition: is this probability bounded … Continue reading
TYI 25: The Automorphism Group of the Symmetric Group
True or False: The group of automorphisms of the symmetric group , n ≥ 3 is itself.
Posted in Algebra and Number Theory, Test your intuition
Tagged Test your intuition, the symmetric group
7 Comments
Test your intuition 24: Which of the following three groups is trivial
Martin Bridson We have three finitely presented groups A is generated by two generators a and b and one relation B is generated by three generators a, b, c and three relations , . C is generated by four generators a, b, c, d … Continue reading
Posted in Algebra and Number Theory, Test your intuition
Tagged Martin Bridson, Test your intuition
10 Comments