

Learn the first 100 digits of Pi - anc2020
http://pitoletters.awardspace.com/

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zacharypinter
In a society with nearly ubiquitous access to the internet how valuable is it
to memorize raw facts? There are a few anecdotes about Einstein not knowing
his phone number and not knowing the number of feet in a mile. His answer was
along the lines of questioning why one should memorize something that can
easily be looked up.

Personally, I find understanding concepts and composing ideas to be far more
valuable. However, I'd be interested in finding out if the memorization of
facts somehow exercised/increased the brain's ability to perform more
(arguably) meaningful tasks.

~~~
anc2020
1) Its a cool party trick - if you can give someone the 82nd digit of Pi in 8
seconds, they'll probably be impressed because you can't really do that using
a conventional method of counting in your head through to that digit of Pi in
such a short time.

2) Brain excercise - things like this will probably help keep your brain
healthy.

> Personally, I find understanding concepts and composing ideas to be far more
> valuable.

Me too, they're not mutually exclusive! I very much take the same view about
memorizing facts and have a generally poor memory. That's partly why this is
cool, I still knew the first 25 digits of Pi effortlessly 2 years after doing
this.

~~~
mattmaroon
You and I go to vastly different parties if that's a cool trick.

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anc2020
Use this to impress your friends by recalling the nth digit of Pi where n <
100

It took me four days I think, 5 words a day, and got me some beer money from
my maths teacher.

Only slight relevance to HN because I'd like to think that its a cool way to
hack number memory.

It works by sorting the 10 digits 0-9 by number of occurrences in the first
100 digits of Pi, and then associating each digit with the corresponding top n
most commonly used letter of the English language (eg. the letter "E" is the
most common English letter).

~~~
shiro
I don't know about English, but in Japanese digits can be pronounced in
several ways and many of them are short (e.g. 1 = "hi", "i", "in" or "hito", 2
= "ni", "nin", "fu", "bu", "pu" or "futa", etc), so it's typical to compose a
meaningful phrase or sentence to memorize various numbers (e.g. phone
numbers).

Remembering pi is a popular game among nerdy kids; I can still recite 200
digits I remembered back in elementary school. Several friends of mime can do
100-800 digits.

For those who can read Japanese, this is one of old ways to remember first 40
digits or so. For 100 digits or more you usually need to come up your own
mnemonics:

産医師異国に向こう/産後厄無く/産婦御社に/虫さんざん闇になく/ご礼には早ういくな

Pronounces: さんいしいこくにむこう/さんごやくなく/さんぷみやしろに/むしさんざんやみになく/ごれいにははよういくな

Corresponds to: 3.14159265 / 358979 / 3238462 / 643383279 / 502884197

Roughly translates to: An obstetrician goes abroad. Postpartum is without
problem. The new mother is to visit a shrine. Crickets are chirping in
darkness. Do not hurry to visit.

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mvid
reminds me of an old rule of thumb:

[http://www.toothpastefordinner.com/031208/how-many-digits-
of...](http://www.toothpastefordinner.com/031208/how-many-digits-of-pi-do-you-
know.gif)

------
likpok
An easier but shorter way:

How I want a drink, alcoholic of course, after the heavy 3 1 4 1 5 9 2 6 5 3 5
chapters involving quantum mechanics. 8 9 7 9

Not as much as 100, but easier to remember.

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kirse
My math teacher in 8th grade used to have PI in one long print-out across the
upper edge of the wall, and I'd usually space out and end up staring at the
wall rather than pay attention. 10 years later I know that Algebra was at
least 18 digits boring.

~~~
pavel_lishin
I had it memorized to 20 digits after buying a book about Pi. After that, I
think I got bored with the topic, but I still remember about that many.

Lemme tell you how many girls this gets me at parties.

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asciilifeform
How(3) I(1) need(4) a(1) drink(5), alcoholic(9) of(2) course(6), after(5)
the(3) heavy(5) lectures(8) involving(9) quantum(7) mechanics(9).

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Avshalom
I rather prefer the Cadaeic Cadenza <http://www.cadaeic.net/cadenza.htm>

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tzury
I'll try to spend my time on other things.

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Timothee
So, I suppose the method is to learn the 20 5-letter words and the key that
goes with it?

The thing is the words don't mean a thing and are not necessarily easy to
pronounce. It doesn't really feel like less work than learning the digits
straight.

~~~
nimbix
Remembering words is different than remembering digits; mainly because
remembering digits is actually remembering words that represent them ("five",
for example). Therefore remembering digits would actually require you to
remember 100 words instead of the current 20 which you then "decompress" into
digits in your head using the simple decoding key.

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ljlolel
I did this a while ago, and better, and posted the code:

[http://www.jperla.com/blog/2008/03/14/learn-100-digits-of-
pi...](http://www.jperla.com/blog/2008/03/14/learn-100-digits-of-pi-at-
lightning-speed/)

~~~
anc2020
Firstly, mapping consonants to digits is hardly original, Derren Brown teaches
the method in one of his books, and its one of the techniques used by people
who do this seriously. Its also not very space efficient because all of your
vowels are counted as whitespace.

Secondly, it would be a lot harder to randomly access the nth digit using your
conventional method because you would also need to be counting the consonants
as you go along through the sequence, rather than just +5 for every word.

