This isn't really a meme
this post was submitted on 19 May 2025
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During lockdown I had a bit of time on my hands so I memorised all the digits of pi in the right order.
I memorized them in numerical order. First there's a bunch of 0s then a bunch of 1s, followed by 2s, and so on.
Yeah but how many 0s do you have before you get to the first 1? I've been working on it but still don't have a definite answer.
I don't know the exact number but it's quite a few of them
Infinite.
You should do alphabetical next.
All... ALL of them?
Hey, me too! I also did e and the Feigenbaum constant, though.
right order
descending primes, right?
Decimal expansion. 3.14 etc
Pi is exactly 3!
so 6?
Tau
Three, no more, no less. Three is the number of pi. Four should not be pi, neither two. Five is right out.
1, 2, 5!
3 sir!
Oh yes! 3!
This beats the approximations used in ancient Sumer (3.1065) and China (3). Try contacting their respective records bodies.
Gotta say, using 3 just feels like giving up due to laziness, even in 1200BC.
Also it's interesting how the Chinese entries basically stop between 1400 and 1949, whereas European names are far more present during this era. Some Japanese ones, too. I wonder how comprehensive this page is.
Rounding pi to 3 is just the engineering way. It's close enough to get the job done and then I don't have to worry about decimal places. However, using pi=3 typically undershoots your calculations, so personally I like to use pi=4
An error margin of less than 5% (even better, biased in a known direction) is more than good enough for plenty of use cases.
An error margin of more than 25% on the other hand, is seldom acceptable.
Nah, it's fine. Trust me I use pi=4 in every calculation I do that uses pi and I haven't ever run into any issues at all
(I'm not that type of engineer, I never do anything with pi)
It's called safety factor
AFAIK the Chinese knew that the value between that of the encompassing shape that meets the circle at tangeants to the inscribed shape whose edges meet the same equidistant points gives us the approximation of pi. So did archimedes, and maybe even the babylonians.
So while a triangle yields about 3 and satisfies the theorem, you could also theoretically draw a 96 gon and 192 gon like Liu Hui for an accuracy of 9x10^5.
Personally I just memorize 22/7 or use the Leibniz infinite series if I have to.
Sometimes zero decimals is enough precision even in 2025…
…but also because of laziness…
Doesn't have the famous
ln(640320³ + 744)/√163
for some reason. Accurate to 14 decimal places I believe which is more accurate than what you need for 99.9% of its applications.
So to avoid memorizing a 15-digit number you'll memorize a 13-digit equation?
More like you memorize that to show off. There are tons of high schoolers that know pi to dozens of digits, it’s not really exciting. But most high schoolers fundamentally don’t understand logs.
It's been said that with 15 decimals, you can calculate the circumference on the observable universe with a precision of the width of an atom.
Not quite, according to JPL https://www.jpl.nasa.gov/edu/news/how-many-decimals-of-pi-do-we-really-need/
15 decimal places, for Voyager 1 - We have a circle more than 94 billion miles (more than 150 billion kilometers) around, and our calculation of that distance would be off by no more than the width of your little finger.
It's also been said that with Pi to just four decimal places you can accurately send a spaceship to one of our nearest neighbouring stars and arrive within one kilometre of your intended target.
In fairness, that was said by me, and I do tend to be full of shit.
This is an exaggeration.
The universe's radius is around 46.5 billion light years (around 4.4 * 10^26 meters), the error introduced of using 15 decimals of pi is around the order of 10^-16. Thus the error of calculating the circumference would be in the order of
8.8*10^26 * 10^-16 = 8.8*10^10 meters
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14 decimal places is more accuracy than you'd ever need.
Consider the size of what you're measuring.
I'm American so you're getting SAE units, deal with it.
If we have a radius of 1", the circumference of my object is 6.283185 or so inches around. Maybe it's 6.283186. the difference between those two numbers is one one hundred thousandths of an inch. About 25 nanometers. Half the size of the smallest bacterium we've ever discovered.
That is with 6 decimal places. With 8 you can measure a circumference with an accuracy to the single atom. Any smaller than that, and you start charging the result by measuring it at all.
Does anyone else really want to write them now just to get an official rejection letter?
If I write them enough and get enough rejection letters, can I then get accepted as the Guinness World Records record holder for most rejections of Guinness World Record records?
Is there a Guiness world record for classes or categories of individuals with the most rejection letters from the Guiness World Records association?
If you pay for it I'm sure they would gladly add it
3.1 I hold the world record for memorizing the shortest length of pi decimals.
- Eat it.
you won after all
This guy engineers
_
I win!
I have memorized fewer digits: " "
Fewer.
Fixed it
You total star!
I hold 2 GWR for the Reddit Secret Santa.
Anyone that participated during a couple years qualified.
Pi for workgroups.
3.11
You could say he was all mixed up, and he didn’t know what (else) to do.
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Every 5y/o is better at copying the Guinness World Records logo.
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