How many decimals of Pi do you remember?

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The discussion revolves around the memorization of Pi, with participants sharing their personal experiences and the number of decimal places they can recall. One user boasts memorizing 150 digits, while others mention knowing fewer, often citing practical reasons for not memorizing more, such as calculators providing sufficient precision. Some participants view memorizing Pi as a fun challenge or a mental exercise, claiming it helps improve memory skills. Others express skepticism about the usefulness of memorizing such a long string of numbers, suggesting that time could be better spent on more practical knowledge. Various mnemonic techniques are discussed, and some users share humorous anecdotes related to their experiences with Pi. The conversation also touches on the broader implications of memory exercises, with some arguing that the act of memorization itself can be beneficial, regardless of the specific content. Overall, the thread highlights a mix of enthusiasm, humor, and practicality regarding the memorization of Pi.
  • #51
I once gave him a piece of paper with \sqrt{2} to 100+ decimal places. He would have me stand there reading the paper while he recited the number - he didn't fake it. He is now responsible for integration of instrumentation and protection (reactor safety) systems in modern nuclear power plants.
 
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  • #52
Tell him to give up on the number and try reciting safety procedures in case of a melt down. priorities man
 
  • #53
tribdog said:
Tell him to give up on the number and try reciting safety procedures in case of a melt down. priorities man


haha tribdog :smile:
 
  • #54
Just to be a complete *******, I'm going to resurrect this post.

By the way: 3.141592653589793238 (18 digits)
 
  • #55
Congratulations, I think we have a winner!

:rolleyes:
 
  • #56
Does 10π count?
 
  • #57
No, Jim, 10π doesn't count. XD
 
  • #58
I used to have a mnemonic system (thanks to my two study hall periods a day in tenth grade), and I ended up memorizing it to about 30 digits. The only ones I remember now are 3.1415926, which is still more than I'll ever need to use...
 
  • #59
HungryFox said:
No, Jim, 10π doesn't count. XD

Doh!
 
  • #60
3.14159265358979

365.24219878

as a lysdexic, I got very po'd memorizing these silly numbers only to find myself getting the last four digits mixed up at the ripe old age of 10. I gave up.

Then in college I discovered you were not supposed to list accuracy past a certain point because it was pointless.

I was very happy that I stopped.

:smile:
 
  • #61
But can you recite all of it - backwards
 
  • #62
3.14 :smile:
 
  • #63
3.141
 
  • #64
22/7
 
  • #65
mgb_phys said:
But can you recite all of it - backwards

Nope. I don't think I can recite anything backwards. I'm a forward thinker.
 
  • #66
I don't understand why people waste their time remembering the decimals of Pi, do something productive that will actually be of value! :rolleyes:
 
  • #67
exactly, one should also memorise e; Universal gas constant, R; Stefan-Boltzmann constant, σ; Speed of light in a vacuum, c; Planck constant, h; The density of air at various altitudes, ρ; etc, etc, etc... :-p
 
  • #68
Used to do 368 digits - can't anymore though, since it was so pointless. I can easily do about 262 now, though.
 
  • #69
Wow, a very tenacious thread with several necropostings all the way from 2003.

I find memorizing a couple of telephone #'s more practical.
 
  • #70
22/7
 
  • #71
I remember 3.14159. Recently I tried to add an additional 5 or 6 numbers onto it during my spare time. I remembered them for a little while, but now I can't remember them.
 
  • #72
I know all of the digits. :P
 
  • #73
I know all of the digits of 22/7 :biggrin:
 
  • #74
I know 6 digits, which is 3 more than I really need.

I know 7 digits of 22/7, which is definitely all I need.
 
  • #75
DR13 said:
I know all of the digits. :P

I know most of them, but I always forget the last one.

Seriously, I inadvertantly memorized 16 digits, since this is the approximate limit of double precision representation of floating point numbers in computers. In the old days, cut and paste was not as easy as today, and it was quicker to just type them in.

3.141592653589793
 
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  • #76
i remember:
pi=3.14159
e=2.718282
thats odd. i remember one more digit of e than of pi.
 
  • #77
3.14159
1.414
299,792,4458 m/s
2.718

That is all I remember off hand
 
  • #78
3.1415926535897932384626 (is that right?), then I am lost. Sometimes I can do more but without confidence.

In a humbling experience, I typed Pi[1,000,000] into Mathematica and it returned a few dozen digits of Pi asking if I really wanted it all. After I told it I wan't kidding it delivered all one million digits in a few seconds.
 
  • #79
if you know pi, you know e:

e_to_the_pi_times_i.png


http://xkcd.com/179/

:)
 
  • #80
Monique said:
I don't understand why people waste their time remembering the decimals of Pi, do something productive that will actually be of value! :rolleyes:
I saw this post yesterday and thought; maybe I should look at this pi! Doesn't take that long memorising raw numbers, now I know:
3.
1415926535 8979323846 2643383279 5028841971 6939937510 5820974944 59

I am sure you know much more digits than that, associated to different things than pi though. I mean 4 digits take ~1 minute to memorize, so the above string should take roughly 15 minutes. Not that much of your life.
 
  • #81
http://zs1.smbc-comics.com/comics/20100130.gif
 
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  • #82
I think the average scientist knows many more digits of pi than the average non-scientist, just because they use the number more often.
 
  • #83
I doubt that there is any scientist who knows less than 3.14.
 
  • #84
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  • #85
ideasrule said:
I think the average scientist knows many more digits of pi than the average non-scientist, just because they use the number more often.
Klockan3 said:
I doubt that there is any scientist who knows less than 3.14.
I add a couple of digits every decade or so. Now in my late 40's, I have 8 or 9 digits memorized.

In actual practice, my calculator has a π button clearly labeled. Instead of spending time memorizing many digits, I have memorized the following:
  • In Excel, =pi() results in π
  • if I don't know whether pi is defined in a given computer language, defining a variable ppii=4.*atan(1.) always works
 
  • #86
I've always known pi up to 15 digits or so, but I was never the type of guy who would memorize pi to a few hundred decimal places. I'd rather memorize the scale of everything in the universe from plank length to the size of our observable universe, the mass and half life of elements, reference numbers in physics, the names of stars, etc.

Edit: Memorized it to 100 digits just now to test my memory.
http://www.greenpeninc.com/memorize/memorize.php
Now trying to memorize e and phi to 100 digits just for amusement. Darn you PF!
 
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  • #87
3.14159
 
  • #88
must get really old now.. i only remember 3 decimals of pi.
 
  • #89
Felipe61 said:
must get really old now.. i only remember 3 decimals of pi.

if you remembered 3----would they still be called decimals?


(i just know one decimal of pi)
 
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  • #90
rewebster said:
if you remembered 3----would they still be called decimals?


(i just know one decimal of pi)
So, you say 3.1?
 
  • #91
Klockan3 said:
So, you say 3.1?

the (one) decimal is the decimal (point/dot) :smile:
 
  • #92
Klockan3 said:
I saw this post yesterday and thought; maybe I should look at this pi! Doesn't take that long memorising raw numbers, now I know:
3.
1415926535 8979323846 2643383279 5028841971 6939937510 5820974944 59

I am sure you know much more digits than that, associated to different things than pi though. I mean 4 digits take ~1 minute to memorize, so the above string should take roughly 15 minutes. Not that much of your life.
I don't think I could do it in 15 minutes if I tried right now. And probably not in an hour even - unless I figure out some clever trick to memorize it. In general though, the way I memorize things is by seeing/using them periodically (i.e., through familiarity). I'm terrible at committing to memory by repeated recitation, like I've seen others do, but that's also probably because I have not put much effort into developing that skill.
 
  • #93
Gokul43201 said:
I don't think I could do it in 15 minutes if I tried right now. And probably not in an hour even - unless I figure out some clever trick to memorize it. In general though, the way I memorize things is by seeing/using them periodically (i.e., through familiarity). I'm terrible at committing to memory by repeated recitation, like I've seen others do, but that's also probably because I have not put much effort into developing that skill.
The trick is to want to memorize, at least for me. If I don't care I will only remember bits but when I focus I can remember just about anything indefinitely. The problem is of course that you can't just conjure up such focus at will.

But are you certain you can't do it? I really wonder how peoples memories works, since they seem to forget just about anything all the time... How do you even study with that disability? It would force you to do the same thing over and over again only to know that it still won't all stick. Kinda like shovelling raw rice with a fork!

Not intending to offend, I really wonder. I'd guess that they are just insanely passionate/motivated about it so they continue on anyway, but it is hard to accept that people have to forget just about everything. Seems so counter intuitive, I am hoping that there is a switch those haven't found yet and if they flip it they would stop forgetting important things.
 
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  • #94
I've memorized thousands of digits of Pi just fine.
But it's the digits to the right of the radix that I have trouble with.

Or.

I've memorized every digit of Pi.
Putting all ten of them in sequence is harder.
 
  • #95
Pi is a lot easier to remember if you calculate with pi basis:
1.0000000000000000000000000000000000000000000000000000000000000000000000000000000000000...
 
  • #96
Pi is around 3-ish.
 
  • #97
Pinu7 said:
Pi is around 3-ish.

3.ish
 
  • #98
pi-70679 said:
I just find that learning pi is a good way to maintain your memory active, plus it's a really good time waster. I found out that now i can remember series of numbers in a lot less time. I just use birthdates, repeating numbers, and my latest, pattern you do with your fingers when you type the keys on the numpad.

I agree. I did the same thing between classes when I was in school towards the end of the semester. I got to 108 places.
I did it as an exercise because I had always told myself I had a terrible memory and I wanted to see how bad my memory was. The semester ended when I was at 108 numbers (I think) and so I stopped the exercise.
There are people who can memorize pi to 10,000 places. I suppose I could have gotten much farther if I made the time to do so. I gained a block of seven numbers daily and that was the 'trick' to it. Also I made it into a rhythm like which is a second trick. I think seven numbers at a time contain a rhythm and that rythms aid memory and this is why groups of seven numbers pop up a lot. I don't mean anything dumb like numerology, I am talking about the rhythm they make and how that aids memory.

I still remember 18 places after the 3.
I think I could have gone much further had I made the effort.


Its a valuable exercise for people interested in their own memory. I didn't read this entire thread but I bet 90% of the comments were like this: "Why do that? It's stupid. That number is not useful to that many places!" The point is not the number but I think that testing one's own memory is useful and it doesn't matter what the object of that memory is. It could be zip codes or sports stats.
 
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