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Dr. Shapiro's Puzzle of the Day

Today's Puzzle

Monday, February 22
I thought of this puzzle on New Year's Day, but decided to save it for 2/22. Here's a way to make the current year from thirty-one 2's:

… OK, maybe that's not very impressive. Your challenge for today is to make 2021 out of as few 2's as possible. You can use addition, subtraction, multiplication, division, exponents, and parentheses. And what the heck, factorials too, if it helps. No concatenation (i.e. you can't just glue two 2's to make twenty-two).

We'll set par at eleven, as that's the best I could do.

   


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Yesterday's Puzzle + Solution

□e a□uent o□cial □y-□shed in cuto□s.
If you ever see a sentence like the above in your browser, it might be because your computer is not displaying ligatures correctly. What should this sentence say? (1000 bonus points if you send me an illustration of the scene.)

Hint Feeling □ummoxed, even ba□ed? □is puzzle is too di□cult? I hope you'll □nd my hint e□ective.

Solution I don't have to pay out any bonus points, because nobody submitted an illustration. Mr. Gregg did suggest that the many pictures online of a shirtless Vladimir Putin fly-fishing would almost fit the bill, but alas, he has not been observed fishing in cutoffs. Putin, that is.

As an aside, I strongly dislike the Th ligature and feel it should not exist.

Congratulations to yesterday's solvers Jacob C., Maddy, Peter M., and the Greggs. Thanks to everybody who made a guess!

About This Site

Though he now teaches mathematics, Dr. (né Mr.) Shapiro's first job in a K–12 school was as a lunch monitor in Davis, CA. It was there that he originated the Puzzle of the Day, even rewarding correct answers with tickets in denominations like "15 points" (though without a clear idea of how he'd ultimately redeem these). Dr. Shapiro's favorite puzzle from this pre-professional era was "Tell me the location of the beehive on this campus."

Ten years later, Dr. Shapiro revived Puzzle of the Day at Proof School, writing each day's puzzle on a name tag. After 600 puzzles or so, he was just starting to feel normal about students reading his chest all the time when campus closed and the puzzle, like the rest of our lives, moved online. New puzzles are posted daily on school days.

Want to catch up on old PotDs? There's an archive currently containing puzzles from March to December 2020.