# A Holiday Puzzle from Primer

December 20, 2021

By

John Bohannon

This post is archived.

References & links may be out of date

It's always an honor to be mentioned in MIT Tech Review. Even better when it is in [the definitive story about Advent of Code](https://www.technologyreview.com/2021/12/17/1042483/puzzle-challenge-coding-christmas/), the annual holiday-themed programming puzzle contest. Like a traditional advent calendar, participants in the Advent of Code receive a daily gift—a programming puzzle which you race to solve—counting down the days to December 25th.

We've always had a puzzle-loving culture here at Primer. In the Before Times when we all worked together in a single office, a new mathematical puzzle would appear on the lunch table each week. It was always remarkable to see a group of people take a break from their busy days solving hard problems...to delight in solving another hard problem!

Here is a Primer puzzle we created for you to enjoy over the holiday.

Cheers from San Francisco!

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**ACROSS**

1: F-down honoree's invention

5: Cat runme.py ⊢ print(open(__file__).read())

6: Second longest word in Moby Dick

B: K-down novel by J-across

C: Mighty source of coding solutions and failures

D: One god's son's mother's famous singer namesake's confirmation name

E: 3E8

H: The second S-across[::-1][1:]

I: GGGGAAGAAAAA translation, probably you

J: Author(BPM 37093 core + solar orbits since birth)

L: Chemical fear induced by 4-down

M: Given name of 5-across

O: Wikipedia's founder's wife's former boss's wife's occupation's South African equivalent

P: Total stopping time of collatz(21845)

Q: J-across' Hackworth occupation

R: Third most common word in US constitution

S: "".join([chr(i) for i in [80, 82, 73, 77, 69, 82]])

T: First-author affiliation of Erdős-Bacon 7's arXiv paper

**DOWN**

2: Size of most famous set of 9-down

3: 700 THz

4: Another name for M-across[-4:]

7: Original L-across[-4:] of S-across

8: Today's annoying version of Simpsons 2F05 NLP feature

9: Well-known canine of historical region south of Edison's rival's birthplace

A: Fearsome extinct member of N-down

E: Capital of "".join([1-across(n) for n in [67, 60, 92, 88, 16]])

F: Name of actinide 1-across(2-down)

G: Most famous product of T-across

J: Vigenére(x, key = Q-across) ⊢ WBLBJEVV

K: Western cross street of J-across homophone Street in 7-down

N: Biden's former boss's wife's alma mater's mascot's family.