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The new year is one of my favorite kinds of numbers: a difference of squares!

2024=(45+1)×(451)=45212

This observation got me thinking about what kinds of numbers can be written as the difference of squares. For example, 3=2212,5=3222, and 16=4202, but it is impossible to write 6 as the difference of squares of integers.

So here’s a little mathematical puzzle to start the new year: Is there a largest number that can not be expressed as the difference of squares? If so, find it. If not, prove no such number exists. Good luck, and happy new year!

mrhonner.com/archives/21614

#2024

Mr Honner · 2024 and Differences of SquaresThe new year is one of my favorite kinds of numbers: a difference of squares! $latex 2024 = 46 \times 44 = (45 + 1) \times (45 – 1) = 45^2 – 1^2 $ This observation got me thinking about…

@phonner Hi Patrick!
I had noticed the difference of 2 squares opportunity for 2024, and it turns out it can done TWO ways:
45^2 – 1^2
and
57^2 – 35^2

@davidradcliffe @KarenCampe Figuring out *when* it's possible also allowd you to determine in how many different ways it's possible.

@phonner @davidradcliffe oooh, I am excited to figure this out!

@phonner @davidradcliffe
So I need both factors of 2024 to be even (or both odd, which won't happen with prime factorization 2^3•11•23
Spoiler ahead....