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Any positive number can be written as a sum of three palindromes

somethingorotherwhatever.com

31–40 of 114 posts

Re: Any positive number can be written as a sum of three palindromes

#31
post #30
post #9

Wonderful wonderful website. What happends to quirky people like this when they leave university and enter the industry?

Is there such a thing as "interactive nonfiction"? Because if not, there should be. Design educational websites this way and watch children learn.

> Is there such a thing as "interactive nonfiction"?

The real physical Universe is interactive nonfiction.

Re: Any positive number can be written as a sum of three palindromes

#32
This reminds me a bit of Fourier transformations from time- to frequency-domain.

Where an arbitrarily complex time-series signal can be accurately represented as the sum of various sine waves.

Except the OP deals with a discretized values, not real-number values, and the OP's approach lets the constituent palindromes start/end at an arbitrary offset, rather than having to be repeated continuously.

Re: Any positive number can be written as a sum of three palindromes

#35
post #30

Earlier quoted context omitted.

Is there such a thing as "interactive nonfiction"? Because if not, there should be. Design educational websites this way and watch children learn.

> Is there such a thing as "interactive nonfiction"? The real physical Universe is interactive nonfiction.

/r/outside

Re: Any positive number can be written as a sum of three palindromes

#36
The most impressive part of this calculator IMHO is the animated text, it dresses up a parsing script and function into a very nice package. I say good job, I wonder how difficult it would be to show a list of all the combinations of three "palindromes" for a given number?

Re: Any positive number can be written as a sum of three palindromes

#39

i'm underwhelmed 77777777777777 +0 +0 =77777777777777

yeah....I don't see why this such an "impressive" trick.

The impressive thing is actually the underlying proof. 40+ pages with lots of edge cases and algorithms for every scenario of any arbitrarily large number.

Re: Any positive number can be written as a sum of three palindromes

#40
For those wondering, this works in every base ≥ 5, according to the original paper: https://arxiv.org/abs/1602.06208v2

Every time I see something like this that is dependent on base-10 representation, I'm always curious to know whether it generalizes, or if it's a quirk specific to base-10 representation. For example, being able to tell if a number is divisible by 2 or 5 by only looking at the last digit.

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