

Ask YC: what happened around September 2009? - andreyf
http://www.google.com/trends?q=collatz&ctab=0&geo=all&date=all&sort=0

======
jwecker
Hypothesis: That's when something triggered inside of Google and it started
tracking the trend (based on a build-up of volume? news? sitting in the queue
for a while), and the steep initial slope is not real but a relic of the graph
going from 0 to whatever their first recorded data point is.

 _shrug_

------
bkow20
Collatz is the last name of a high school athlete who made track and field
headlines at around that time.

------
cruise02
It will get a spike from today's XKCD, which will sadly probably be higher
than the spike it receives when the thing is finally solved.

------
SamAtt
Given Lothar Collatz was German and he died in September of 1990 I'd assume
something about his death (a remembrance of some kind) triggered it. Most of
the searches are from Germany along with neighboring Switzerland and Denmark.

Also note someone posted a picture of him on his Wikipedia page in Sept. '09
which is the first time the page had been touched by a non-bot in 15 months
([http://en.wikipedia.org/w/index.php?title=Lothar_Collatz&...](http://en.wikipedia.org/w/index.php?title=Lothar_Collatz&action=historysubmit&diff=312437360&oldid=285135406))

(He's also mentioned in the Sept. 2009 issue of the European Mathematical
Society Newsletter for what it's worth)

------
garply
I'm not sure if I'm more interested in the explanation for this data or in how
you came across it.

~~~
dfranke
Prompted by today's XKCD, most likely.

------
misterbwong
Here's some info from wikipedia in case you're wondering what the XKCD strip
is about: <http://en.wikipedia.org/wiki/Collatz_conjecture>

