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themathguy
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20 Sep 2025, 2:34 pm

What is your favorite math result/theorem?

Mine is the Tweedledum and Tweedledee principle from Winning Ways for your Mathematical Plays by Conway, Berlekamp, and Guy. Informally, it says that any partizan combinatorial game has a value of zero if the players can swap moves and the game is still worth the same value.



kokopelli
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27 Sep 2025, 6:57 pm

I like the proof that there is no limit to the number of consecutive integers there are without a prime.

That is, for any N, find integers i, i+1, i+2, ..., i+N-1 such that none of the integers are prime.

The best part about it is that many people who aren't mathematicians can often understand it.



Justin Time
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05 Oct 2025, 11:20 am

All numbers (integers) are interesting.

If they weren't then there is a smallest non interesting number. Which makes it interesting.


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Justin Time
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09 Oct 2025, 2:25 am

More seriously.....

If you randomly permute N objects the expected number to remain unmoved is 1.
I might have expected it to vary as N changed.


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traven
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09 Oct 2025, 2:29 am

QED