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Room Code

Title text: Sorry to make you memorize this random string of digits. If it helps, it can also double as a mnemonic for remembering your young relatives' birthdays, if they happened to have been born on February 5th, 2018.

Explanation

This explanation may be incomplete or incorrect: Created by a RANDOM STRING OF UPPERCASE LETTERS - Very bare-bones explanation. Do NOT delete this tag too soon.

Cueball and Megan are on vacation or otherwise traveling, and receive a code for their hotel room. Megan gives a seemingly nonsensical and unhelpful mnemonic by which Cueball can remember it... which, inexplicably, actually helps Cueball to remember the code. Cueball becomes VERY angry on realizing this.

The first three prime numbers are actually 2, 3, and 5. So this technique easily identifies the first two digits "02". "05" is slightly wrong because it's not the second prime number, it's the third. And "18" is more wrong because it's not actually a prime number, it's 2 x 3 x 3.

So the mnemonic itself doesn't really provide the method for remembering the code. Instead, figuring out how to apply the bogus mnemonic will reinforce your memory of the code.

The title text points out that the code is also similar to a date in MMDDYY format, so if you happen to have a relative who was born on February 5, 2018, the memorized code will help you remember this date if using said date format.

Transcript

[Megan is standing next to Cueball, who is holding a phone or a note in his hand. Each one has a suitcase on the out-facing side of them.]

Cueball: Okay, I need to remember that the room code is 020518.

[Closeup on Megan who has her palm raised.]

Megan: Easy -- just memorize it as "the first three prime numbers, if you realized you couldn't remember what came after 2 and started to panic and get them increasingly wrong."

[Beat panel of Megan and Cueball standing with no border.]

[Megan and Cueball still standing.]

Megan: ...Are you mad because that actually works?

Cueball: Why is memory like this?

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