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Tanya Khovanova's Math Blog

blog.tanyakhovanova.com

Mathematics, applications of mathematics to life in general, and my life as a mathematician.

Math

’10’15’20’25
Posts
964 from 19 Oct 2007 to 21 Oct 2026
Posting
weekly (40 in the last year)
Kind
personal blog
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https://blog.tanyakhovanova.com/feed/

2026 30

  1. Sleeping Beauty and ChatGPT
  2. Returning Soldier Effect
  3. An Asteroid Walk: The Answer
  4. 2026 MIT Mystery Hunt
  5. Immensely Questionable Tests
  6. Round Table Coin Game
  7. A Referendum Puzzle
  8. Three Mathematicians and One Book
  9. A Voucher Puzzle
  10. Swap Lectures with Homework
  11. Truck Driver
  12. Recreational Mathematics in the Age of AI
  13. Cats and Sausages
  14. Permutation-Based Labeled Chip-Firing
  15. Killer Puzzle
  16. AT, BAT, and CAT
  17. ChatGPT Jokes About ChatGPT
  18. Coin Parity
  19. Fingers on One Hand
  20. Five Sages
  21. A New Laugh from Alexander Karabegov
  22. Icosahedron
  23. A Billiard Table
  24. Friday
  25. My First Book
  26. Two Fathers
  27. Hat Swaps
  28. Minimal 3-Regular Penny Graph
  29. How to Read a Math Paper
  30. The Weight of a 1-Kilo Brick

2025 22

  1. Missing 5
  2. Two Points on a Cube
  3. A New Twist in a Famous Problem
  4. 2025 MIT Mystery Hunt
  5. Happy Fractal Holidays!
  6. A Math Quiz
  7. New Gozinta Boxes Trick
  8. Each Point has Three Closest Neighbors
  9. Dividing Estate
  10. A Story about a Scam
  11. Card Dealing Math
  12. Do Nothing
  13. Egg, Banana, Apple, Walnut, Tangerine, and Avocado
  14. Friends on a Walk
  15. Non-Identical Identical Triplets
  16. Pavel Likes Pets
  17. Pledge of Honor
  18. Gold, Silver, and Bronze Coins
  19. Identical Triplets
  20. Russian-American Race
  21. The Game of SET for Groups (Part 2), jointly with Andrey Khesin
  22. Foams and the Four-Color Theorem

2024 48

  1. Happy 2025!
  2. Identical Twins
  3. A Puzzle from the Möbius Tournament
  4. Red, Yellow, and Green Hats
  5. Square out of a Plus
  6. The Game of SET for Groups (Part 1), jointly with Andrey Khesin
  7. Foams Made out of Felt
  8. Make 60 by Using the Same Number Thrice
  9. Alexander Karabegov’s Puzzle
  10. Good Puzzles Are the Reason I Check Facebook
  11. Clean and Dirty Sisters
  12. Cheese and Butter at the Fall Tournament of the Towns
  13. Sam’s Locks
  14. A Hat Puzzle with a Twist
  15. Help the Fisherman
  16. Gelfand Seminar
  17. Fibonometry
  18. Fibonacci Tricks
  19. Grigori Perelman’s Puzzle
  20. The 5-Card Trick, the 4-Card Trick, and the 3-Card Trick
  21. The 5-Card Trick and Information, jointly with Alexey Radul
  22. Fractal Word Search
  23. Conway’s Absent King Trick
  24. Thinking Inside the Box
  25. Pass-Fail
  26. My Favorite Shoes
  27. Another Symmetry Puzzle
  28. Is It Possible?
  29. An Alternator Coin Puzzle
  30. 2024 MIT Mystery Hunt
  31. Calculus in Life
  32. Tesseracts and Foams
  33. Three L-tetraminoes
  34. Why We Need Foreign Languages
  35. Hundred Colors of Math
  36. Jokes from the Audience
  37. Find the Side
  38. My Students’ Jokes
  39. Fudge Likes Meatballs
  40. My Family’s Jokes
  41. Two Lovely Puzzles
  42. Some Recent Puns Added to My Collection
  43. Some Recent Jokes Added to My Collection
  44. Guess the Number in One Question
  45. Icosahedron’s Resistance
  46. Ikigai
  47. Mini Stupidity
  48. The Angry Wife

2023 68

  1. My Unique Christmas Card
  2. A Probability Puzzle from Facebook
  3. Four Sheep
  4. Back to Coins
  5. Sos
  6. A Quadrilateral in a Rectangle Solution
  7. Polyomino Cutting Solution
  8. A Quadrilateral in a Rectangle
  9. How Many Cows Are Left?
  10. EvenQuads at PRIMES STEP
  11. Solomon’s Knot
  12. From Estonia Math Olympiad
  13. Find the Disappearing Bits
  14. An English Quine
  15. Polyomino Cutting
  16. A Balanced Cube
  17. A Quadratic and its Derivative
  18. Find the Murderer
  19. Brunnian Links at MOVES
  20. Another Bunch of Math Jokes
  21. More Childish Jokes
  22. Mafia in a Math Battle
  23. Candy Game
  24. Next Bunch of Jokes
  25. Punny Answers
  26. Childhood Memories
  27. Borders of Strips
  28. Some More Math Jokes
  29. Nostalgia
  30. The Linking Number
  31. The Power of a Computational Proof: Uncrossed Knight’s Tours Continued
  32. Balls in Boxes
  33. Klein Bottles without Holes, or How to Crochet Through
  34. The Odd-one-out Dilemma
  35. A Bribe for a 5-Star Review
  36. The Teacher Asks…
  37. My April Fool’s Story
  38. Family Bush
  39. Cooperative Dedicated Liars
  40. The Vicious Dragon
  41. A Puzzle from Alex Ryba
  42. Alexey’s Puzzle
  43. MIT Mystery Hunt 2023
  44. Move Two Matches to Get the Largest Number
  45. Don’t Read This Sentence
  46. A Chess Puzzle
  47. Wonderful John Conway
  48. Touching Eternity
  49. Escher’s Subgroups
  50. Noisy Violinists
  51. Follow Your Heart?
  52. A Silent Parrot
  53. A Puzzle Courtesy of Dick Hess
  54. An Affair
  55. Refresh Your Greek to Solve a Puzzle
  56. A New Version of an Old Joke
  57. Dividing Chores
  58. Towers
  59. Whitney Umbrellas
  60. The Dark Secret of Escher’s Shells
  61. Pay Lives to Touch Glasses
  62. Why Would I Know Where the Sugar is?
  63. Putin’s Waste
  64. A Fresh Irregular-Chessboard Puzzle
  65. Move Two Matches
  66. A Facebook Challenge
  67. In Search of a Tribonacci Building
  68. The Raven’s Hat

2022 79

  1. Tanya Khovanova's Math Blog » Blog Archive
  2. A Random Pair of Friends
  3. The Struggles of Chessland
  4. Uncrossed Knight’s Tours
  5. Logicians Walk into a Cafe
  6. YuMSh Olympiad
  7. Rulers to the Rescue
  8. The Unstoppable Truck Driver
  9. Dear Parents of Math Geniuses
  10. Flying Eggs
  11. How Much Would You Pay Me to Read Your Email?
  12. A Goat
  13. Find the Largest and the Smallest
  14. Gnomes Solution
  15. More Math Jokes
  16. A Hat Trick
  17. Sierpińsky Instead of Seifert
  18. The Lomonosov Tournament: Games Contest
  19. Poisoned Wine
  20. Sleeping Beauty and Tuesdays
  21. The Sleeping Beauty Problem Amplified
  22. Sleeping Beauty Wants the Prize Money
  23. Toblerone
  24. Three, Five, and Seven have Different Remainders When Divided by Three
  25. The Big Point Theorem
  26. Should There Be Separate Math Competitions for Girls?
  27. Fresh Cute Logic Puzzles
  28. Another Nine-Dots Puzzle
  29. A Number Theory Problem from the 43rd Tournament of Towns
  30. Thinking Inside and Outside the Box
  31. A Mathematical Model for Gender Bias in Mathematics
  32. A Logic Puzzle about Sophists
  33. My New Favorite Russian Plate
  34. Brick Puzzle
  35. Cool New Coin Problems
  36. Tricky Probabilistic Arguments
  37. What are Your Math Research Interests?
  38. More Gnomes
  39. Shapovalov’s Gnomes
  40. The Books for My Dog
  41. My Gender
  42. Maximum Egalitarian Cost in the Stable Marriage Problem
  43. I Will Be Hanged
  44. Scooter Ideas
  45. Looking for a Well-Educated Gentleman
  46. Whitehead Links for Ukraine
  47. Hyperbolic Surfaces for Ukraine
  48. The Pinocchio and Oihcconip Sequences
  49. My Vision for Number Gossip
  50. Retouched Picture of John Conway
  51. Best of the 2022 MIT Mystery Hunt
  52. Crocheting Away My Pain
  53. Arnold’s Advice
  54. Already or Have
  55. The 1978 Ukrainian Math Olympiad
  56. Calculating the Average Age in Secret
  57. Weird Ways to Improve Your Erdős Number
  58. Fun with Latin Squares
  59. The Barber Paradox and English Tenses
  60. The Age of Consent
  61. Reversible Tetrahedra
  62. Kyiv Olympiad, 1978
  63. The Problem with Two Girls
  64. Martin Gardner’s Surprise
  65. Ready for My Knot Theory Class
  66. Seven, Ace, Queen, Two, Eight, Three, Jack, Four, Nine, Five, King, Six, Ten
  67. Zipper Math
  68. Meta Solving a Probability Puzzle
  69. Borromean Rings
  70. My Moscow State University Transcripts
  71. A Card-Dealing-Trick Sequence: Persistimis Possessiamo
  72. Hats and Time
  73. Preparing for My Knot Theory Class
  74. My Math Teacher versus My Mother-in-law
  75. Fish Puzzle
  76. 2013 MIT Mystery Hunt
  77. Archimedes Helps Again
  78. My Computational Linguistics Olympiads
  79. A Dingo Ate My Math Book

2021 29

  1. Happy 2022!
  2. Continue the Sequence: 2, 4, 6, 8
  3. A Power Problem
  4. Some Computer and Math Jokes
  5. What would John Conway Do?
  6. Snowball Sentences
  7. 2021 MIT Mystery Hunt
  8. A Splashy Math Problem Solution
  9. The 41-st Tournament of the Towns
  10. Clock Hands
  11. Five Mondays
  12. Four Wizards
  13. Mostly Probability Jokes
  14. Trying to Crochet the Impossible
  15. My Virtual Stars
  16. The Top Fifty Largest Numbers that Start a Sequence in the OEIS
  17. Joint-Groups Sudoku
  18. The Stable Marriage Problem and Sudoku
  19. What’s in the Name? Solution
  20. 1 is the Only Square-free Square
  21. What’s in the Name?
  22. Number Gossip on Steroids
  23. Continue the Sequence: 742, …
  24. I am Hooked on Star Battles
  25. Swiss Cheese Star Battle
  26. Our Familect Story
  27. A Splashy Math Problem
  28. I Miss John Conway
  29. The Anniversary Coin

2020 18

  1. Discover the Rule
  2. Build an All-red Cube
  3. Penney’s Game and Groups
  4. Confirming the Labels of Coins in One Weighing
  5. The Blended Game
  6. Monetizing My Blog
  7. The No-Flippancy Game
  8. 2020 MIT Mystery Hunt
  9. SET Tic-Tac-Toe
  10. Coronavirus and Gender
  11. Among Mathematicians
  12. Coronavirus in NYC
  13. Anchored Rectangles
  14. John Conway, the Presenter
  15. My Last Picture of John Conway
  16. Mathy Review of the 2019 MIT Mystery Hunt
  17. US Coronavirus Numbers
  18. A Game with the Devil

2019 18

  1. The Game of Chessnot
  2. The Padlock Puzzle
  3. Meta Logic
  4. Recovery Jokes
  5. My New Favorite Probability Puzzle
  6. A Probability Puzzle
  7. What are the Numbers?
  8. Another Weird Test Question
  9. Day and Night
  10. How Old is Everyone?
  11. Cube Sudo-Kurve
  12. Emissary Puzzles
  13. Cave Lioness
  14. My Phone
  15. The Halfsies
  16. Less Annoying Hyperbolic Surfaces
  17. Fast Thinking
  18. Happy 2019!

2018 26

  1. Puzzle Ninja
  2. Two Dice
  3. My 1975 IMO Team
  4. An Orchestra Puzzle
  5. The Annoyance of Hyperbolic Surfaces
  6. 3-Inflatable Permutations
  7. Symmetries of k-Symmetric Permutations
  8. 3-Symmetric Graphs
  9. 3-Symmetric Permutations
  10. Mafia Logic Puzzle
  11. Shapes of Symbols in Latin Squares
  12. Another Cool Coin-Weighing Problem
  13. I am on TEDEd
  14. A Self-referencing Multiple-Choice Question
  15. Innisfree Garden
  16. Looking for the Cutest Answer
  17. Richard Guy
  18. My Last Visit with John Conway
  19. A Crypto Word Search for G4G13
  20. Punny Puzzles at the MIT Mystery Hunt
  21. Scam Jokes
  22. Solutions to Geometry Puzzles from the 35-th Lomonosov Tournament
  23. Mathy Puzzles at 2018 MIT Mystery Hunt
  24. Trump and Pirates
  25. My 2018 MIT Mystery Hunt Puzzles
  26. Why

2017 25

  1. A Scooter Riddle
  2. Mathy Jokes
  3. A Gender-Biased Puzzle
  4. Who Lives in the White House?
  5. A Domino-Covering Problem
  6. More Computer Jokes
  7. Derek Kisman’s Ex Post Facto
  8. Fair-Share Sequences
  9. 2015 Coin Problem Solution
  10. 2014 Math Festival in Moscow
  11. My First Husband with My Third Husband
  12. The Best Writing on Mathematics 2016
  13. Which One Doesn’t Belong?
  14. A Waterfall of my Feelings
  15. Winning Nim Against a Player who Plays Randomly
  16. The Hidden Beauty
  17. Can You Solve My Problems?
  18. Playing with Pascal’s Triangle
  19. My Favorite Problems from the Moscow Math Olympiad 2016
  20. My Last Visit to Smullyan
  21. Trump’s Ban is Good for Trump’s Business
  22. A Random Scale Solution
  23. Russian and American Children
  24. A Homogeneous Date
  25. Deserve to Steal

2016 36

  1. Alternators: People and Coins
  2. A Random Scale
  3. Chameleon Coins
  4. Even More Jokes
  5. Russian Honor Code
  6. Who Is Left?
  7. A Faulty Scale
  8. How Many Triangles?
  9. Should You Apply to PRIMES?
  10. Alexander Shapovalov Crosses a River
  11. 3-Pile Nim as an Automaton
  12. The Longest Optimal Game of Nim
  13. Replace Question Marks
  14. Geometry Puzzles from the 35-th Lomonosov Tournament
  15. Your Deal is Better than my Deal
  16. The Reuleaux Tetrahedron
  17. Who is Guilty?
  18. A Travel Puzzle
  19. Really Big Numbers
  20. A River-Crossing Puzzle
  21. An Orthogonal Quadrangle
  22. The Battle I am Losing
  23. A Frog Puzzle
  24. Is My Bank Smart Enough?
  25. Late Homework
  26. An Asteroid Walk
  27. More Jokes
  28. Mikhail Khovanov at Kvant
  29. The Ford Circles Game
  30. Weighted Mediants
  31. Ringiana
  32. Where is My Team Now?
  33. I do not Trust My Gut Feeling Anymore
  34. My Poster Boy
  35. Problems with Problems with Two Children
  36. How to “Predict” the Gender of a Future Child

2015 51

  1. Plan B
  2. Two Fake Coins
  3. The Intended Answers
  4. Evil Bananas
  5. The First Moscow Olympiad
  6. Ode to Menopause
  7. Time for Jokes
  8. How Many Letters?
  9. What is the Answer to This Question
  10. The Wythoff’s Game Evolution Graph
  11. Finding My Own Niche
  12. Who Proved Theorem 5?
  13. Who Wants to Be a Bad Mathematician?
  14. Family Ties
  15. My Six Jobs
  16. The Advantage of a Window
  17. From Tanks to Coins
  18. Tanya Velikanova
  19. Magic SET Hypercube Continued
  20. The Secretary Problem with a Sliding Window
  21. From Graphs to Games
  22. Meta-Solving Multiple Choice
  23. Dodgers, Liars and Pathological Truth-Tellers
  24. Tanya Time
  25. Truth That Lies
  26. Tanks at the 2015 All-Russian Math Olympiad
  27. Kvantik 2013
  28. Kvantik’s Problems Solutions
  29. Hidden Birthdays in the Winning Ways
  30. Genius at Play
  31. The Dying Art of Mental Math Tricks
  32. Statistics Jokes
  33. The Best Writing on Mathematics 2014
  34. Kvantik’s Problems
  35. The Miracle of my CPAP Machine
  36. Where is the Party?
  37. Stern-Brocot Trees
  38. Andrei Zelevinsky’s Problems
  39. My Sleep Study
  40. Puzzling Grades Resolved
  41. My Number
  42. The Emperor and His Wizards
  43. 2015 Moscow Math Olympiad
  44. Fear of Alzheimer
  45. A New Question about Old Coins
  46. PRIMES Dominates High School Research
  47. Puzzling Grades
  48. “What Does the Police Say?”
  49. Pampam
  50. Laughing at 225
  51. Nothing is on Hold by the arXiv

2014 43

  1. Walking Lessons
  2. Skyscrapers (Sum)
  3. Jokes That Clicked
  4. ApSimon’s Mints Investigation
  5. My Blog is Still under Attack
  6. No Averages Solution
  7. Intel ISEF Mathematics Awards 2014
  8. Some Jokes
  9. Crypto Word Search II
  10. Crypto Word Search
  11. Is 2014 Awesome or Not?
  12. Hong Kong Elementary School First Grade Student Admission Test Question
  13. Free Fibonacci Sequences
  14. Stuck at 225
  15. De-stressing Jokes
  16. My Blog is under Attack
  17. My Ancestry
  18. No Averages
  19. Lazy Jokes
  20. A Logic Quiz
  21. ApSimon’s Mints
  22. Masturbating With an Accent
  23. Computer Security Jokes
  24. Hat Puzzle: Create a Distribution
  25. Linear Algebra on a Mission Impossible
  26. Nim Automaton
  27. Kolmogorov Student Olympiad in Probability
  28. IQ Migration
  29. Math Kangaroo’s Logic Puzzle
  30. Express 6
  31. The Virtue of Laziness
  32. Beer Jokes and Hat Puzzles
  33. How Well Do You Know Your Dice?
  34. My New Yellow Road
  35. Salary Negotiations
  36. The Three Light Bulbs Puzzle
  37. Liars and Their Motivation
  38. Reverse Bechdel Test
  39. More Math Jokes
  40. Mathy Problems from the 2014 MIT Mystery Hunt
  41. Ambiguities in Logic
  42. Prepare for the Hunt
  43. A Bump on My Yellow Road

2013 46

  1. Intellectual Jokes
  2. arXiv’s Police
  3. Industry vs Academia
  4. An Irresistible Cannonball
  5. My Life: An Update
  6. Lost a Digit in Kilos
  7. Alexey’s Conversations
  8. Four More Papers
  9. Gelfand’s Centennial
  10. My Exercise Plan
  11. Smart Brake Lights
  12. Parallel Weighings Solution
  13. Ode to My Digital Scale
  14. Discussing a Problem from the Moscow Olympiad
  15. Next Tanya Khovanova
  16. Missing Coin
  17. Fraternal Birth Order and Fecundity
  18. My New Favorite Hat Puzzle
  19. Samples from My AMSA Homework
  20. Parallel Weighings
  21. Was I Dead?
  22. I’ve Lost 10 Pounds
  23. A Problem from the Moscow Olympiad
  24. Happy Nobel Prize Winners
  25. Four Papers in Three Weeks
  26. Integers and Sequences Solution
  27. My Yellow Road to Healthy Weight
  28. Skyscrapers
  29. Vampires versus Mathematicians
  30. Integers and Sequences
  31. Weighing Coins during the Mystery Hunt
  32. My Weight
  33. February Jokes
  34. Solving In the Details
  35. Cambridge Waldo
  36. Open Secrets Revealed
  37. Turnary Reasoning
  38. The Most Difficult Hunt Puzzle: 50/50
  39. In the Details
  40. Something in Common
  41. Portals
  42. Random Walk
  43. Open Secrets
  44. Apologies
  45. Children’s Riddle
  46. Affirmations

2012 46

  1. Halving Lines
  2. I am on the Air
  3. Helpmate
  4. Me and Chess
  5. Challenge Problems
  6. Nerdy and Flirtatious Jokes
  7. 2012!
  8. Why I Eat
  9. Three out of Three
  10. PRIMES-USA
  11. Number Gossip is Back
  12. A Visit to Smullyan
  13. A Measure of Central Symmetry
  14. Great Ideas that Haven’t Worked. Yet.
  15. Taking Sudoku Seriously
  16. Judging the Tail
  17. Number Gossip Has Been Killed
  18. Conway’s Subprime Fibonacci Sequences
  19. Kvant for Younger School-Children
  20. My Take on Perelman
  21. World Championship Puzzles
  22. Nerdy Jokes from the Russian Web
  23. Math Girls
  24. Picasso’s Diagnosis
  25. My Psychotherapy
  26. Making Connections
  27. A Visual Proof
  28. Did You Notice?
  29. A Median Coin
  30. A Poison Duel
  31. Hiring the Smartest People in the World
  32. Interlocking Polyominoes
  33. A Mysterious Bracelet
  34. Rubik’s Cube Game
  35. Names in Boxes
  36. Nerdy Jokes from the Web
  37. Guessing the Suit
  38. My Love Affair with Sugar
  39. Dragons and Kasha
  40. Approaching the AIME Strategically
  41. Why Americans Should Study the Moscow Math Olympiads
  42. Apples in a Basket
  43. Designing a Magic Trick
  44. Saturated Domino Coverings
  45. Sergeism and Weight Loss
  46. Binary Bulls Explained

2011 88

  1. Binary Bulls without Cows
  2. The Most Colorful Independent Set
  3. Jokes from the Web
  4. A Russian Internet Linguistics Olympiad
  5. Rotor-Router Networks
  6. Weighings and Puzzles
  7. A Probabilistic Paradox
  8. Weathered Steel Weave
  9. Another Russian Olympiad
  10. Apples and Oranges
  11. Infinite Deductible
  12. Two Riddles
  13. Internet-Search-Friendly Names
  14. The Oxford Murders
  15. More Nerdy Humor
  16. You Are Welcome to Contact Me, But …
  17. Jewish Problems
  18. Plagiarism
  19. This is Not a Consultation
  20. David Bernstein’s Paradox
  21. The Rings of Power
  22. Hiding Behind
  23. Star Trek TNG Science Quiz
  24. Time for Nerdy Humor
  25. Too Good at Spider Solitaire
  26. What Sequences Sound Like
  27. Broom Bridge
  28. Sleeping Beauty and Mondays
  29. Sleeping Beauty Meets Monty Hall
  30. Tripling a Triangle
  31. The Sleeping Beauty Problem
  32. Big Numbers
  33. Finchley Central
  34. The Best Math Problem Solver is a Girl
  35. Pretty Cells
  36. Polite Gender Bias
  37. All Roads Lead to Philosophy
  38. I Was Attacked
  39. A Chat with a Calculator
  40. May the Force Be with You!
  41. Tell Time Looking at the Night Sky
  42. Math as an Aphrodisiac
  43. Translated from Russian
  44. Complexity of Periodic Strings
  45. Leon Vaserstein’s Problems
  46. Recent Geeky Jokes
  47. Large Numbers, Few Characters
  48. A Nerd’s Way to Walk Up the Stairs
  49. Moscow Math Olympiad
  50. How Much is Two and Two?
  51. Self-Mutilating DNA
  52. Freedom and Diamonds
  53. Averaging Averages
  54. A Wrong Solution
  55. The Oral Exam
  56. The Hidden Agenda Revealed
  57. Enemies and Friends
  58. A Math Exam’s Hidden Agenda
  59. Good Math Research Projects for High School
  60. A Son Named Luigi
  61. Eat to Live
  62. The Cookie Monster Problem
  63. Fractional Voting Power
  64. How Many Hats Can Fit on Your Head?
  65. Computer Jokes
  66. Subtleties of Lies
  67. Why Are We Losing Female Mathematicians?
  68. Should You Date a Mathematician?
  69. The Horsemen Sequences
  70. Puzzles for Lawyers
  71. Criminal Probability Theory
  72. Fermat’s Room
  73. The Wizards’ Hats
  74. Mr. Jones
  75. Tetrahedron Problems
  76. 86 Conjecture
  77. The Second IMO Gold Girl
  78. The Art of Checking
  79. Goodbye 29, Hello 42
  80. A Math Guide to the MIT Mystery Hunt 2011
  81. Mutant Sudoku
  82. Two Planes Keep Flying
  83. Naum Bernstein’s Jokes
  84. Two Planes
  85. Dangers of Auto-payments
  86. From a Puzzle to a Magic Trick
  87. Sergey Markelov’s Best
  88. On the Perfidy of Negative Numbers

2010 94

  1. More Nerdy Jokes
  2. Pie
  3. Adjustments to Medical Bills
  4. Math, Love and Immortality
  5. Lida Goncharova — The First Gold IMO Girl
  6. Problem Design for Multiple Choice Questions
  7. Blindfolded Charades
  8. Sparsity and Computation
  9. Blindfolded Men Getting Together
  10. Darth Vader and Social Networks
  11. Dear Spammer
  12. Choices or No Choices
  13. How Early Can You Teach Math to Kids?
  14. Romeo and Juliet
  15. Repairing a Point Mutation
  16. The Sayings of Mikhail Zhvanetsky
  17. Smoking Vampires
  18. November Jokes
  19. Heavier or Lighter
  20. Ten Coins
  21. PRIMES and RSI
  22. One-Way Functions
  23. Five Fridays, Five Saturdays and Five Sundays
  24. Automatic Differentiation
  25. Modern Coin-Weighing Puzzles
  26. Decycling Graphs and Terrorists
  27. Marriage Proposals, Or How I Learned to Say No
  28. My Sister
  29. A Truel
  30. The Weights Puzzle
  31. The Random Sequence
  32. Dirt Sells
  33. Rock, Paper, Scissor
  34. Nim-Chomp
  35. Math Careers and Choices
  36. Divisibility by 7 is a Walk on a Graph. II
  37. Milk
  38. The Sexual Side of Life
  39. Women, Science and The Right Tail of a Bell Curve
  40. Hats and Rooms. Take II
  41. The First Western IMO
  42. How to Live Longer
  43. Hats and Rooms
  44. Shannon Entropy Rescues the Tuesday Child
  45. Interns or Slaves?
  46. Why I Quit Academia
  47. Cars That Run on Water
  48. My First Polymath Project
  49. George Hart
  50. Scary Coins
  51. A Tuesday Quiz
  52. My Dr’s Orders: Hit on Men
  53. Conway’s Circle
  54. Equal Numbers
  55. 007
  56. Father’s Maiden Name
  57. Russian Solidarity
  58. On Mice and Coins
  59. USAMO 2007, Problem 5
  60. The Rise of MIT
  61. The Best Math Blogs
  62. An Algebra Text Book
  63. Raymond Smullyan’s Magic Trick
  64. Conditional Probability and “He Said, She Said”
  65. Sons and Tuesdays
  66. The Second Doomsday Lesson
  67. My Name
  68. Rainbow Graphs
  69. Fibonacci Salad
  70. More Trick Problems
  71. Hidden?
  72. L-Reptiles
  73. Food XOR Drink
  74. Baron Münchhausen and the Riemann Hypothesis
  75. A Woman in Numbers
  76. Latin Squares Game
  77. A Son Born on Tuesday
  78. Months’ Lengths
  79. Lennart Green
  80. The Greatest Mathematician Alive
  81. Yet Another Coin Weighing Problem
  82. Sara’s Birthday
  83. Math at the MIT Mystery Hunt 2010
  84. Conway’s Recipe for Success
  85. Nerdy Jokes
  86. Wise Men Without Hats
  87. Women in Numbers
  88. Office Lottery Pool
  89. The Expected Return on Lotteries
  90. Magic Set Hypercube
  91. How to Boost Your Guessing Accuracy During Tests
  92. Solving Problems with Choices
  93. What’s Missing?
  94. To Guess or Not to Guess?

2009 109

  1. Lottery as an Investment
  2. Should You Check Your Answers During Tests?
  3. Problem Solving and Research
  4. Physics Jokes
  5. The Odder One Out
  6. It Has Been Two Years
  7. Gelfand’s Memorial
  8. Octopus Problems
  9. An Older Woman, A Younger Man
  10. Beliefs that Might Save Your Life
  11. Why Modulo 11?
  12. HMNT 2009
  13. Hassan’s Horses
  14. No Odd One Out
  15. Ringamatics
  16. Turing Tests’ Race
  17. Geometric Transformations
  18. Not So Humble Pi
  19. Can You Force Your Parents to Pay for Your College Expenses?
  20. Gelfand’s Gift
  21. The Odd One Out
  22. A Math Guide to the MIT Mystery Hunt
  23. Mythematics
  24. Another Coins Sequence, jointly with Alexey Radul
  25. The Defining Moment
  26. Papaya Words and Numbers, jointly with Sergei Bernstein
  27. Points on the Plane
  28. Why is the South Pole Colder than the North Pole?
  29. Heard on the Street
  30. Gay Polygamy
  31. Archive Labeling Sequences, jointly with Gregory Marton
  32. Fine Dining with a Pizza Puzzle
  33. Misunderstanding between Databases
  34. Propagation Networks: A Flexible and Expressive Substrate for Computation
  35. The Dirtiest Math Problem Ever (Rated R)
  36. Link, Blogroll and Review Exchanges
  37. Contact Me
  38. Will We Get to a Palindrome?
  39. Mom, Thank You Very Much
  40. Frog Puzzle
  41. Physics Puzzle, by Levy Ulanovsky
  42. Unrevealing Coin Weighings
  43. Divisibility by 7 is a Walk on a Graph, by David Wilson
  44. Propagation Networks
  45. Countable Wise Men with Hats
  46. America’s Got Talent
  47. Destinies of Numbers
  48. Unfairness
  49. Is Shopping Good for the Economy? Lessons from “Settlers of Catan.”
  50. Authors’ Contributions Conjecture
  51. A Miracle Equation
  52. What Does It Take to Get Accepted by Harvard or Princeton?
  53. Fast Food Research?
  54. Coins Sequence
  55. Langton’s Ant’s Life
  56. The 2009’s Doomsday is Saturday
  57. Fire Hazard
  58. Turning Numbers Inside Out
  59. It’s All Greek to Me
  60. Evolutionarily Stable Strategy
  61. Ratso’s Story, by Sue Kelman
  62. More Linguistics Puzzles
  63. Mathematics at MIT, Harvard, Princeton
  64. Can You Count to 100?
  65. Children and Happiness
  66. A Puzzle in Psilvanian
  67. “Female Mathematician”
  68. My Toilet Invention
  69. The Solution to the Swahili Puzzle
  70. Nerdy Wedding
  71. An Experiment Inspired by Vladimir Arnold
  72. Oleg Kryzhanovsky’s Problems
  73. A Killer Puzzle
  74. Linguistics Puzzles for Middle School
  75. Brown Sharpie of Courtney Gibbons
  76. Abstruse Goose’s Million Dollar Idea
  77. Is There Hope for a Female Fields Medalist?
  78. Phonetics Puzzles
  79. Sue’s Mortgage Puzzle
  80. Multiplication Problems
  81. USAMO and the Election, by J.B.
  82. Password Adventures
  83. The Flip-Flop Game
  84. Multiple Choice Proofs
  85. Subtraction Problems, Russian Style
  86. AMC, AIME, USAMO Contradiction
  87. My Most Memorable Math Mistake
  88. Does Taller Mean Smarter?
  89. Stackable Letters
  90. Sunrise Mistake
  91. Romanian Masters in Mathematics
  92. A Hole for Jews
  93. Can Someone Be Straight?
  94. Fly Droppings on Your Pizza
  95. Linguistics Puzzles
  96. Math without Breaking a Nail
  97. Celebrating with a Consenting Adult
  98. Sexacholics at MIT Mystery Hunt
  99. Fire, Help!
  100. Dow Jones Index and Presidents
  101. Linguistics, Arrogance, KGB
  102. Computational Linguistics Olympiad
  103. Odd Fibonacci and Odd Lucas Numbers
  104. All the Dirt on Number 5
  105. Thue-Morse Odiousness
  106. Richard and James
  107. Is Anyone Watching?
  108. Political Analysis of USA-Russia Relations through Russian Anecdotes
  109. Metasolving AMC 8

2008 79

  1. My Next Step
  2. My Paper Road Block
  3. Confusion about Vampires
  4. Probability Theory for Crooks
  5. China Girls Math Olympiad
  6. Another Two Coins Puzzle
  7. Statistics Homework
  8. My IQ
  9. The Women and Math Program
  10. Safer Parking
  11. Two Coins Puzzle
  12. How I Chose My Math Adviser
  13. Eye Color and Math Ability
  14. Understanding Philosophy Through Jokes
  15. Hanged or Electrocuted?
  16. The Designated Listener
  17. The Word “Love” and Tomatoes
  18. What’s Hidden?
  19. It’s All My Fault
  20. Perfect Math Notation
  21. A Room Full of Women
  22. Linear Algebra for Pirates
  23. Borrowing Money
  24. The Right Time to Have Children
  25. Library Puzzle
  26. Four Puzzles for the Price of One
  27. A Math Puzzle that Sounds like a Computer Science Puzzle
  28. Math Career Predictor
  29. Linear Algebra at a Math Olympiad
  30. Designing Bill Gates’ Bathroom
  31. Who Should Have Kissed Whom
  32. Girls’ Angle
  33. The Polynomial Game
  34. Recounting Cats
  35. (x, why?) Webcomics
  36. High Price of Bounced Checks
  37. October Geek Jokes
  38. Back-to-School Funny Pictures
  39. An Organic Puzzle
  40. Through-the-Looking-Glass Monsters
  41. Remember Your Primes
  42. Why are Manhole Covers Square?
  43. The Symmetriad
  44. Mid-Summer Status Report
  45. Grand Tour Puzzles
  46. Challenging Start
  47. A Math Paper by Moscow, U.S.S.R.
  48. A $1,000 Typo
  49. Floating Zipcars
  50. Genetics Paradox
  51. Tetramodules in the Air
  52. Fraternal Birth Order Threatens Research into the Genetics of Homosexuality
  53. The Symmetries of Things
  54. Flexible Zipcar Algorithm
  55. Funny Pictures
  56. Conway’s Wizards Generalized
  57. Sing Away Your Snoring
  58. Reason Number 37 not to Trust NJ Transit
  59. Simplified Wizards Puzzle
  60. I am a Computer Addict
  61. A Very Special Ten-Digit Number
  62. John Conway’s Wizards
  63. The Mathematical Path to the Right Husband
  64. Does Alcohol in Teens Lead to Adult Woes?
  65. Masturbation and Prostate Cancer
  66. Divisibility of Odd Fibonaccis
  67. Catalog Choice
  68. Blog Spam
  69. Spring Math Humor
  70. Does Spanking Children Affect their Future Sex Life?
  71. IHateSecurityQuestions
  72. Does Paying with a Credit Card Make You Fatter?
  73. Do Gas Stations Need Your Zip Code?
  74. Resisting Databases
  75. Numbers Need Sponsors
  76. Quantifying Favors
  77. MIT Mystery Hunt Functions
  78. My Fantasy Future of 2+2: a Copyright Nightmare
  79. The “Why the Heck?” Diet

2007 9

  1. Evaluating Exercise DVDs
  2. Teaching our Children to Lose the Lottery
  3. Jumping Off the Cliff
  4. Autobiographical Numbers
  5. My Paper Road to Academia
  6. Fridays the 13th
  7. My Mid-life Crisis
  8. 9 Divides no Odd Fibonacci
  9. Welcome to my Math Blog