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davidlowryduda.bsky.social
DLD
@davidlowryduda.bsky.social
Mathematician, programmer, and various other things at various other times.
September 8, 2025 at 7:30 PM
Can one then show that 1 = 2, say by manipulating a - (a + 1) = 0 into a = a + 1, adding 1 to both sides, and subtracting a? No! The reason why is that LEAN knows that subtraction in the naturals isn't subtractive. (Or rather it doesn't think that it is subtractive).

(3/3)
September 8, 2025 at 7:30 PM
The proof in LEAN is very simple: tell it to use 0. What happens behind the scenes is that, in LEAN, 0 - 1 = 0 (when considered in natural numbers). I think this is because it's convenient to have naturals closed under basic operations.

(2/3)
September 8, 2025 at 7:30 PM
At this morning's opening session of the code4math opening (preview.scholarlattice.org/collections/...), I learned that in LEAN one can prove the following theorem:

There exists a natural number a such that a - (a + 1) = 0.

(1/3)
preview.scholarlattice.org
September 8, 2025 at 7:30 PM
+1 for Secret Mall Apartment
April 16, 2025 at 7:42 PM
It definitely contributes to math-as-mysticism, incantations done by all-knowing mages that is intractable to mere mortals. But this is far from the truth! And we want more people to recognize that mathematical thinking is useful and approachable and worthwhile!
December 20, 2024 at 2:20 PM
And also this was the source of bsky.app/profile/davi...
This is the Fibonacci zeta function. Actually, it's the odd-indexed Fibonacci zeta function, but that's ok.

davidlowryduda.com/odd-fibonacci/
December 18, 2024 at 12:23 PM
I wrote about this some here.

davidlowryduda.com/paper-fibona...
Paper: The Fibonacci Zeta Function and Continuation
I have a new preprint on the odd Fibonacci zeta function.
davidlowryduda.com
December 18, 2024 at 12:22 PM
I just submitted "The Fibonacci Zeta Function and Continuation" (or as I think of it it, Fibonacci Zeta Function I) to the arxiv. Cheers to my collaborators Eran Assaf, Chan Kuan, and Alex Walker.

I feel like I've accomplished something, so I will goof off with my daughter for a while.
December 18, 2024 at 12:21 PM
Reposted by DLD
Pro tip for folks who use beamer: Turn off the nav symbols!
\setbeamertemplate{navigation symbols}{}

🧪⚛️🧮
Hey #MathSky, I have questions:

1. WHAT are these little buttons for?
2. Have you EVER actually used them?
3. Have you ever seen ANYBODY use them?
4. WHY are they still around?
5. In what year do you think they will finally go away?
6. What other things in life are like this? (I can think of a few)
December 14, 2024 at 10:54 PM
Reposted by DLD
Hey #MathSky! 👋 Interested in learning how to leverage #computing to advance your mathematics research and teaching? You may be interested in the @aimathematics.bsky.social sponsored "Leveraging GitHub and AI for Mathematics Research and Teaching" PEP: jointmathematicsmeetings.org/meetings/nat...
Join Us at the Joint Mathematics Meetings - The Largest Mathematics Gathering Globally
Discover cutting-edge mathematical advancements and network with industry leaders at the world's largest mathematics meeting!
jointmathematicsmeetings.org
November 18, 2024 at 11:27 PM
Thanks. I've never heard of Ologs before.
December 7, 2024 at 5:14 PM
I'm very interested in the different notetaking systems that mathematicians, scientists, programmers, and engineers use. This is talked about somewhere, right?

I'm looking for more than "I use a notebook" or "I use [app name]". I want to know how people actually use and organize their notes.
December 6, 2024 at 4:05 PM
This is the Fibonacci zeta function. Actually, it's the odd-indexed Fibonacci zeta function, but that's ok.

davidlowryduda.com/odd-fibonacci/
December 4, 2024 at 5:59 PM
I appreciate the tip, thanks!
March 8, 2024 at 8:08 PM
Hello, World!
March 8, 2024 at 3:48 PM