• 2 Posts
  • 18 Comments
Joined 1 year ago
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Cake day: June 20th, 2023

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  • Fortunately containers can get bigger =)

    While we aren’t all the same, there’s a difference between things that require holding 8 complicated things in mind at once, and things that require a little language learning and the intelligence to solve a crossword. This is closer to the latter - like doing a crossword in Spanish. You need to know a bunch of little things, but learning them is basically all tedium and not brilliant insights. (Taking these puzzles, creating a dozen new variants, and solving all of those probably does require managing a lot of complexity. But to understand the work of others, is not so bad)














  • An arithmetic miracle:

    Let’s define a sequence. We will start with 1 and 1.

    To get the next number, square the last, add 1, and divide by the second to last. a(n+1) = ( a(n)^2 +1 )/ a(n-1) So the fourth number is (2*2+1)/1 =5, while the next is (25+1)/2 = 13. The sequence is thus:

    1, 1, 2, 5, 13, 34, …

    If you keep computing (the numbers get large) you’ll see that every time we get an integer. But every step involves a division! Usually dividing things gives fractions.

    This last is called the somos sequence, and it shows up in fairly deep algebra.



  • For the uninitiated, the monty Hall problem is a good one.

    Start with 3 closed doors, and an announcer who knows what’s behind each. The announcer says that behind 2 of the doors is a goat, and behind the third door is a car student debt relief, but doesn’t tell you which door leads to which. They then let you pick a door, and you will get what’s behind the door. Before you open it, they open a different door than your choice and reveal a goat. Then the announcer says you are allowed to change your choice.

    So should you switch?

    The answer turns out to be yes. 2/3rds of the time you are better off switching. But even famous mathematicians didn’t believe it at first.