Archive for the ‘Puzzle Hunts’ Category.

10th May 2023, 01:14 pm

Every year, I used to blog about math-related puzzles from that year’s MIT mystery hunt. However, I want to skip this year. I participated in the hunt, and a few of the puzzles I saw were not good enough. Moreover, the puzzles had boring steps or were inelegant. I am not motivated to sift through every math puzzle in the hunt and check its quality.

This year, instead of cataloging all the math puzzles, I will present a short list of puzzles from the hunt that were recommended to me by others. Most of these puzzles are unrelated to math, but I checked them out, and they seem cool.

After the hunt, I asked two people about their favorite puzzles. Both of them mentioned Showcase. Looking at it, I know why. I’ll give you a hint: this puzzle will appeal to people doing competitive programming.

Here are some other recommendations.

- Scicabulary, this is a word puzzle.
- Natural Transformation, you are presented with some very structured images.
- Collage, this is a funny farm.
- Cute Cats, you are presented with many images, some of them with cats.
- Hall of Archaeology, this is a Nikoli-type puzzle.
- Museum Rules, this puzzle looks like a children’s picture book.
- This Puzzle is Just Another Regular Cryptic, this is a cool cryptic puzzle.
- Parsley Garden, you are presented with a grid of words.
- Dispel the Bees, you are presented with crossword clues.

Share:

21st April 2022, 02:43 pm

Every year, after the MIT Mystery Hunt was over, I would go through all the puzzles and pick out the ones related to mathematics. This year, I didn’t feel like doing it. Besides, I think it is more important to collect quality puzzles rather than all the puzzles by topic. So my new collection is the puzzles recommended to me, which I might like.

I start with math and logic puzzles.

I continue with computer science.

I carry on with some non-math fun.

I conclude with the plot device round. All the puzzles in this round are relatively easy. But our team got stuck on them until we realized that we already had the answer, which was not a single word. Here are some of the puzzles that were specifically recommended.

Share:

11th January 2022, 12:01 pm

I usually collect puzzles related to math after each MIT mystery hunt. I just discovered that I never reviewed the 2013 hunt, though I started writing the post. Plus, I knew the puzzles of that year better than other year’s puzzles: I was on the writing team. Not to mention, the hunt had some real gems.

I start with mathematical puzzles:

- In the Details by Derek Kisman. This is one of my favorite puzzles ever involving evil fractal word search. I even posted the puzzle and the solution on my blog.
- Integers and Sequence by me. I used my number gossip database to include cool facts about numbers. The numbers form sequences, as hinted by the title. (The title had a typo: sequences should be plural.)
- Permuted by Victoria de Quehen, David Roe, and Andrew Fiori, with illustrations by Kiersten Brown, Turing machine by Adam Hesterberg, and ideas from Daphna Harel and David Farhi. The puzzle has many mini puzzles related to different areas of mathematics.
- Basic Alphametics by David Farhi and Casey McNamara. I love this puzzle and often give it to my students.
- 50/50 by Derek Kisman; server by Ben Buchwald. This is a multi-layered statistics puzzle with a fantastic design and should be included in statistics books. It was the most difficult puzzle of the hunt. Unfortunately, the link is broken, but luckily, I blogged about this puzzle.

Logic puzzles:

- Color Sudoku by Byon Garrabrant and Tanya Khovanova.
- Turnary Reasoning by Timothy Chow, Alan Deckelbaum, and Tanya Khovanova. The puzzle looks like a mixture of chess, checkers, and Magic the Gathering.
- Paint-by-Symbols by R.M. Baur, based on an idea by Eric Wofsey. As the name suggests, this is a paint-by-numbers puzzle.
- Time Conundrum by David Farhi. Many people loved this puzzle.
- Portals by Palmer Mebane. Ten interconnected Nikoli-type logic puzzles. It is a very difficult puzzle with a fantastic design; I immensely enjoyed testing it.
- Random Walk by Jeremy Sawicki. Another Nikoli-type masterpiece that I enjoyed.
- Lineup by Charles Steinhardt and Palmer Mebane. Another paint-by-numbers with a twist.
- Agricultural Operations by Palmer Mebane, based on an idea by Dan Zaharopol. Kenken with a mathematical twist. It might be the most mathematical puzzle in the hunt, a masterpiece that I greatly enjoyed.
- Lojicomix by Robyn Speer and Alex Rozenshteyn; art by DD Liu.

Computer science puzzles:

- This Page Intentionally Left Blank by Dan Gulotta, with some help from Robyn Speer. Another puzzle worthy of textbooks: It covers different ways how information can be hidden.
- Halting Problem by Dan Gulotta. You have to analyze programs in different languages: the programs are designed to run for a VERY LONG time.
- Evolution by Karen Rustad; idea and some screenshots by Asheesh Laroia. A puzzle about email clients.
- Git Hub by Robyn Speer. A git repository puzzle.
- Call and Response by Asheesh Laroia, Glenn Willen, and Charles Steinhardt. You are given only an IP address.

Crypto puzzles:

- Infinite Cryptogram by Anders Kaseorg.
- Security Theater by Sean Lip. I enjoyed this puzzle that uses various ways to encrypt information.
- Open Secrets by Tanya Khovanova and Robyn Speer. A puzzle with many famous ciphers.
- Caesar’s Palace by Jason Alonso, with casino-formatting by Robyn Speer, clue phrase by Adam Hesterberg. An encrypted crossword which I greatly enjoyed.
- Famous Last Letters by David Farhi. Another encrypted crossword.

Word puzzles:

- Split the Difference by R.M. Baur and Eli Bogart. A puzzle with cryptic clues, which I enjoyed.
- Mind the Gaps by R.M. Baur and Eli Bogart. You are given an empty rectangular grid without black cells and cryptic crossword clues.
- Changing States by Charles Steinhardt, Robyn Speer, and David Roe. A lovely easy puzzle which I enjoyed tremendously.
- Wordplay by Ken Fan, Matt Jordan, Tanya Khovanova, Derek Kisman, and Ali Lloyd. You are given grouped cryptic clues.
- Plead the Fifth by Eli Bogart and R.M. Baur, based on an idea by Eric Wofsey. An elegant puzzle with several AHA moments.
- CrossWord Complex by Robin Baur, Eli Bogart, and Jeff Manning. The puzzle consists of six crosswords that turn into serious mathematics.
- Ex Post Facto by Derek Kisman; idea by Tom Yue. An inventive multi-layered crossword, which I greatly enjoyed.
- The Alphabet Book by Halimeda Glickman-Hoch and Robyn Speer, based on an idea by Bryce Herdt. Loved it.
- Funny Story by Lilly Chin, Eric Mannes, and Jenny Nitishinskaya.
- Loss By Compression by Charles Steinhardt and Robyn Speer. A cool puzzle.
- A Regular Crossword by Dan Gulotta, based on an idea by Palmer Mebane. A hexagonal crossword with regular expressions as clues.
- A Set of Words by David Farhi. You are given several boggle grids. I loved this puzzle very much.
- Czar Cycle by Yasha Berchenko-Kogan. This is a weird puzzle that uses English, Russian, and Greek alphabets.

Misc puzzles:

- Substance Abuse by David Reiley and Timothy Chow, with assistance from Jill Sazama, Shrenik Shah, and Glenn Willen.
- Puzzle-Regarding Vehicle by Katie Steckles, Paul Taylor, and Ali Lloyd. An interesting and difficult puzzle.
- A Walk Around Town by Sean Lip, Ludwig Schmidt, and Freddie Manners, with help from Mary Fortune and Jonathan Lee. The puzzle looks like a walk around town but has more to it. The idea is awesome.
- Something in Common by Dan Gulotta and Tanya Khovanova.
- Too Many Seacrest by Robyn Speer. A cool and funny puzzle.
- Analogy Farm by Robyn Speer, Adam Hesterberg, and Alan Deckelbaum; additional code by Anthony Lu and John Stumpo. A superb analogy game. I loved it so much that after we solved it, I came back and resolved it myself. I am not sure it works anymore, though.
- I Can See For Miles by David Roe, based on an idea by Charles Steinhardt. You are given aerial views of buildings. I usually do not like puzzles that involve googling, but using google maps in this puzzle made me feel like I am flying around the world.

Other puzzles I worked on:

- Cambridge Waldo by Tanya Khovanova starring Ben Buchwald, Adam Hesterberg, Yuri Lin, Eric Mannes, and Casey McNamara. The goal of this puzzle was to allow a chance for people to go for a walk around Cambridge. I am not sure we were successful: it could be that people used Google street-views to solve this puzzle.
- Lost in Translation Gaetano Schinco, Natalie Baca, and Tanya Khovanova. You are given tangrams.
- Linked Pairs by Herman Chau and Rahul Sridhar, with crosswords by Adam Hesterberg, Dan Gulotta, and Jenny Nitishinskaya, Manya Tyutyunik, and Tanya Khovanova. You are given three crossword grids, each with two sets of clues.
- Magic: The Tappening by John Wiesemann, with help from Dan Gulotta and Tanya Khovanova.

Share:

19th December 2021, 06:23 pm

Each year I look at the MIT Mystery hunt puzzles and pick ones related to mathematics, logic, and computer science. I usually give additional comments about the puzzles, but this year’s titles are quite descriptive. Let’s start with mathematics.

Now Nikoli-type logic puzzles. I really enjoyed “Fun with Sudoku” during the hunt.

And computer science.

Share:

9th August 2021, 01:24 pm

- 4, 6, X, 9, 10, 12, 14, 15, 16
- 1, 2, 6, 24, 120, X, 5040, 40320, 362880
- 2, X, 3, 4, 7
- 1, 2, 3, 4, 5, 6, X, 8, 9, 153, 370, 371
- X, 2, 3, 4, 5, 6, 7
- 6, 28, 496, 8128, X, 8589869056, 137438691328
- 0, 1, 1, X, 4, 7, 13, 24, 44, 81

This is the puzzle I designed for yesterday’s event at the Museum of Mathematics. This puzzle is without instructions — figuring out what needs to be done is part of the fun. Solvers are allowed to use the Internet and any available tools. The answer to this puzzle is a word.

Share:

23rd June 2020, 04:30 pm

## 2020 MIT Mystery Hunt

Every year I write about latest MIT Mystery Hunt puzzles that might be appealing to mathematicians. Before diving into mathy puzzles, I would like to mention two special ones:

Unfortunately math wasn’t prominent this year:

- Food Court—This is a probability puzzle that is surprisingly uninspiring. There is no mystery: the puzzle page contains a list of probability problems of several famous types. But this puzzles can find great use in probability classes.
- Torsion Twirl—Mixture of dancing and equations. I love it.
- People Mover—Logical deduction at the first stage.

On the other hand, Nikoli-type puzzles were represented very well:

- The Ferris of Them All—Several different Nikoli puzzles on a wheel.
- Toddler Tilt—Not exactly a Nicoli puzzle, but some weird logic on a grid, some music too.
- The Dollhouse Tour—Not exactly a Nicoli puzzle, but some weird logic on a grid, some pictures too.
- The Nauseator—The first part of the puzzle is a huge nonogram.
- Domino Maze—A non-trivial Thinkfun puzzle.
- Backlot—Finding a path on a grid with a fractal structure.
- Whale—Variation on Rush Hour.

Some computer sciency puzzles:

Cryptography:

A couple of puzzles with the mathy side hidden:

Share:

24th March 2020, 07:23 pm

Every year I review MIT mystery hunt from a mathematician’s point of view. I am way behind. The year is 2020, but I still didn’t post my review of 2019 hunt. Here we go.

Many puzzles in 2019 used two data sets. Here is the recipe for constructing such a puzzle. Pick two of your favorite topics: Star Trek and ice cream flavors. Remember that Deanna Troi loves chocolate sundae. Incorporate Deanna Troi into your puzzle to justify the use of two data sets.

On one hand, two data sets guarantee that the puzzle is new and fresh. On the other hand, often the connection between two topics was forced. Not to mention that puzzle solving dynamic is suboptimal. For example, you start working on a puzzle because you recognize Star Trek. But then you have to deal with ice cream which you hate. Nonetheless, you are already invested in the puzzle so you finish it, enjoying only one half of it.

Overall, it was a great hunt. But the reason I love the MIT mystery hunt is because there are a lot of advanced sciency puzzles that can only appear there. For example, there was a puzzle on Feynman diagrams, or on characters of representations. This year only one puzzle, Deeply Confused, felt like *AHA, this is the MIT Mystery hunt*.

Before discussing mathy puzzles I have to mention that my team laughed at Uncommon Bonds.

I will group the puzzles into categories, where the categories are obvious.

Mathy puzzles.

Here are some logic puzzles, in a sense that Sudoku is a logic puzzle.

- Lantern festival—A cool mixture of Slitherlinks and Galaxies.
- Invisible Walls.
- Place Settings.
- Middle School of Mines—Minesweeper.
- Moral Ambiguity—Nonograms with a twist.
- Connect Four—Mastermind. There was a strong hint that the extraction step was also mastermind. My team spent some time trying to mastermind the ending, until we backsolved. The extraction step was not mastermind. The final grid in the puzzle had the word CODE written in red. It corresponded to letters CDEO found at that location. Given that the letters were not in alphabetical order, it gave the ordering, which didn’t exist in the puzzle. Anyway, you can see that I have a grudge against this puzzle. This could have been a great puzzle. But it wasn’t.
- Schematics—Tons of Nikoli puzzles of different types.

Now we have logic puzzles or another type, where you need to draw a grid. These are puzzles of the type: Who lives in the White House?

Now we have logic puzzles or yet another type, where you need to figure out which statements are true and which are false.

Now some cryptography.

And some programming.

Miscellaneous.

Share:

10th April 2018, 06:20 pm

This is a math blog, but from time to time, I write about other things. Today I have something to say about puns, which I adore.

I also like gym, but rarely go there: it doesn’t work out. I stopped using stairs, because they are up to something. I wanted to learn how to juggle, but I don’t have the balls to do it.

I work at MIT, the work place with the best dam mascot: Tim the Beaver. My salary is not big, and I stopped saving money after I lost interest. I’m no photographer, but I have pictured myself outside of MIT too. I am a mathematician, which is the most spiritual profession: I am very comfortable with higher powers. I praise myself on great ability to think outside the box: it is mostly due to my claustrophobia. I am also a bit of a philosopher: I can go on talking about infinity forever.

I would love to tell you a joke. I recently heard a good one about amnesia, but I forgot how it goes.

My biggest problem is with English. So what if I don’t know what apocalypse means? It’s not the end of the world!

I never get tired of puns and here is my list of pun puzzles from the MIT Mystery Hunt:

Share:

19th February 2018, 04:36 pm

I was on the writing team for the 2018 MIT Mystery Hunt. I am pleased that the hunt got very positive reviews from the participants. I spent tons of hours working on the hunt and it is good that folks liked it. I edited and tested a lot of puzzles. Here is my review of these year’s puzzles that are math-related.

I already posted an essay about the puzzles I wrote myself. Four of my five puzzles are math-related, so I am including them below for completeness. I will mention the topic of each puzzle unless it is a spoiler.

I start with Nikoli-type puzzles. Four elegant Nikoli-type puzzles were written or cowritten by Denis Auroux. In all of them the rules of the logic are stated at the beginning. That means the logic part doesn’t contain a mystery and can be solved directly.

- Good Fences Make Sad and Disgusted Neighbors (by Denis Auroux). You can guess by the title that this puzzle was in the emotions round corresponding to sadness and disgust. This is an interesting variation on the hexagonal Slitherlink. This is a relatively easy puzzle.
- Shoal Patrol (by Denis Auroux and James Douberley). Each grid is a combination of Battleship, Minesweeper, and a loop puzzle. These are difficult, but satisfying puzzles. The extraction step is not mathematical and not completely trivial.
- Submarine Patrol (by Denis Auroux and James Douberley). This is a 3D version of Shoal Patrol.
- Hashiwokakuro (Count your bridges) (by Denis Auroux). This is a mixture of Hashi and Kakuro. I enjoyed the puzzle while I tested it. The extraction is trivial.
- A Learning Path (by Tanya Khovanova and Xavid). This is a path logic puzzle that was targeted for new hunters. It contains self-referencing hints and solving techniques.

There were several puzzles that were very mathematical.

There were also some math-related or computer-sciency puzzles.

- The Next Generation (by Colin Liotta). I enjoyed being an editor of this puzzle.
- Disorientation (by Alex Churchill). This puzzle has a beautiful visual component.
- Message in a Bottle (by Nathan Fung). The puzzle doesn’t look like it has something to do with mathematics, but my testing of it was very satisfying. I guessed from the start what it was about.
- Self-Referential Mania (by Justin Melvin). Self-referential logic puzzle, which I enjoyed editing.
- Bark Ode (by Elizabeth French, Justin Melvin, and Erica Newman). The pictures are so cute.
- Executive Relationship Commandments (by Robin Deits, John Toomey, and Michele Pratusevich). I didn’t see this puzzle until after the hunt. I wish I could have tested this puzzle with my son Alexey, who is a computer scientist.

There were also several decryption puzzles:

- Word Search (by Tanya Khovanova). A crypto word search.
- Texts From Mom (by Elizabeth French and Justin Melvin ). A text enciphered with emojis.
- Marked Deck (by Colin Liotta and Leland Aldridge). One of my favorite puzzles. Hunters received a physucal deck of cards that was laser cut. You can buy the deck at Etsy. The art in this puzzle is beautiful, but the puzzle also has a non-trivial decryption step.

Share:

10th February 2018, 06:41 pm