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Dr. Shapiro's Puzzle of the Day

Today's Puzzle

Wednesday, February 3
Of the 340,000+ entries in the On-Line Encyclopedia of Integer Sequences, just 99 have the distinction of being tagged as "dumb". (Thanks to Peter V. for making me aware of this.)

Here's an example of a dumb sequence: 3, 2, 1, 7, 4, 1, 1, 8, 5, 2, 9, 8, …. What is it? Why, it's the digits of π alternating with the digits of e!
Today I have three questions for you about dumb sequences.

  1. The numbers 10, 170, 2730, 43690, … are called screaming numbers. Why?
    Hint A non-decimal number base is involved.

  2. The sequence 2, 3, 4, 5, 7, 16, 20, 22, 26 has an entry. So does the same sequence with 26 removed. These are labeled as the "American" and "British" versions. What are they?
    Hint Each number represents a letter.

  3. Which sequence goes 1, 2, 3, 95, 98, 2000, 7, 8, 10?
    Hint This is computer-related. A competing sequence (which is either not in the OEIS, or not tagged as dumb) recently got its first new term in twenty years: 11.

   


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Yesterday's Puzzle + Solution

I woke up at 6:00 this morning and knew today's puzzle had to honor the holiday... but how?

Ah. Here we go.

Tell me the color of the fast boi seen at left. Make your answer three words, if you please: _____ ___ ____.

Hint

Solution The answer is "hound dog gray"... a spoonerism of Groundhog Day! The hint was meant to get you two-thirds of the way there—if you know that one of Elvis's hit songs was "Hound Dog".

Congratulations to yesterday's solvers Ena, Peter V., Maddy, Inca, Mrs. Gregg, and Jason. 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.