
 The On-Line Encyclopedia of Integer Sequences - gkop
http://oeis.org/
======
qdot76367
I had the honor of having lunch with Dr. Sloane once. By the end, the paper
tablecloth was COVERED in sequences scrawled in pen. He was grinning and
telling everyone at the table about different properties and new sequences
being worked on.

OEIS was awesome before that, but seeing how much he really, really loves
sequences made it even better. You can feel the love between every comma.

~~~
leif
This warms my heart.

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jlgreco
If you make a plot of how many different sequences a particular number appears
in in this database, a rather interesting pattern emerges.

Some numbers appear frequently, as you would expect (primes, numbers 1 off
from prime, etc) while others appear infrequently, but in general there is a
downward trend as the numbers become larger. That is all expected; what isn't
expected is that there seems to be a break between common numbers and uncommon
numbers. A very distinct break. The theory is that social prejudices towards
certain bases and certain numbers have caused mathematicians to find more
sequences with numbers that they "like" than those that they don't. So for
example, numbers that look neat in base 10, say "3333" or "4444" get special
treatment and tend to occur in more sequences.

The paper on this weird distribution is rather accessible, I recommend it:
[http://arxiv.org/abs/1101.4470](http://arxiv.org/abs/1101.4470) Page 4 has
the pretty plot.

~~~
dmunoz
Numberphile did an episode about Sloane's Gap [0].

[0]
[https://www.youtube.com/watch?v=_YysNM2JoFo](https://www.youtube.com/watch?v=_YysNM2JoFo)

~~~
jlgreco
Aye, the Numberphile video is fantastic; that's actually where I first found
out about this. :) All their videos tend to be great; they're done by the same
film-maker that does the "Periodic Videos" youtube channel, Brady Haran.

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petercooper
It's weird because this awesome site (well worth checking out) has been
submitted about 10 times here and never got any comments except for this time:
[https://news.ycombinator.com/item?id=2496629](https://news.ycombinator.com/item?id=2496629)
.. it's like there's not much to say about integer sequences or something ;-)

Quippery aside, there was an interesting question on Mathematics Stack
Exchange about Arthur C Clarke's _The 9 Billion Names of God_ and the OEIS:
[http://math.stackexchange.com/questions/34237/the-9-billion-...](http://math.stackexchange.com/questions/34237/the-9-billion-
names-of-god)

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baddox
I always enjoy the self-referential sequences.

[http://en.wikipedia.org/wiki/On-
Line_Encyclopedia_of_Integer...](http://en.wikipedia.org/wiki/On-
Line_Encyclopedia_of_Integer_Sequences#Self-referential_sequences)

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alexcweiner
My one professor is a rather big fan of it. several students in my class have
sequences on it, and some are even "sequence" administrators

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kroger
I spent hours on the OEIS having fun. I like to convert numerical sequencies
to sound to see how they sound. Some sound bad but some sound pretty good. I
wrote a little bit about this here:

[http://pedrokroger.net/2013/05/how-does-pascals-triangle-
sou...](http://pedrokroger.net/2013/05/how-does-pascals-triangle-sound/)

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blueblob
This site could be _much_ nicer if they used javascript to render the latex
equations, most of them are already in latex anyways (without the $ signs).

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PilateDeGuerre
An encyclopedia? Is that like a wiki?

 _I kid, I kid_

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brianpgordon
That site is more than 15 years old. I don't know how anyone is still
discovering it for the first time.

~~~
crntaylor
Today I listened to the album _The Rise and Fall of Ziggy Stardust_ for the
first time. It was released in 1972. Is it really that bewildering to you that
not everyone has seen everything that exists already?

~~~
jamesbritt
Wow. So what did you think? (I heard the album a year or so after it came out.
Curious how it sounds to someone today.)

~~~
crntaylor
I really enjoyed it. It's an odd experience, listening to an album that old
and that well known for the first time, because almost inevitably you will
have heard some of the songs before without realising where they were from. A
couple of times I recognized intros or riffs but couldn't quite place them -
probably from movies, advertisements, or just hearing them on the radio.

You also have to try and shed yourself of the intervening 40 years of musical
and social development, to try and get a sense of why this album created such
a buzz when it was released for the first time (context - I'm about 30 years
old, so I wasn't even born until 10 years after this was released, and wasn't
socially/musically aware until about 25 years after it came out.)

