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**They are rich results. I repeat: RICH RESULTS.**

Rich snippets? Rich cards? Enriched results? As per Google's announcement the other day (http://bit.ly/2BfBSRu) they have settled on the name

**rich results**for this type of feature in the search results, and the rich-result-ification of Google's structured data documentation is under way. :)

#richresults

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**Horizontal Range of the Flow of Fluid through a Hole**

The following animation shows how the pressure of a column of water determines the range of flow of water through a hole of a container.

Since the pressure of the water column is directly proportional to its height, the pressure decreases with the loss of height and so does the horizontal velcocity of the water that comes out.

*Flash Modelling Credit:*Vascack Vladimir

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**A wonderful appearance of a wonderful number**

Suppose you take the complete graph on n vertices and randomly assign a number between 0 and 1 to each edge. Call these numbers

**lengths**. Suppose they are independent and uniformly distributed random variables.

Now look for a

**spanning tree**: a bunch of edges that include all the vertices, but don't form any loops. Find a

**minimal**one: one where the sum of all the edge lengths is as small as possible!

*What's the total length of all the edges, in this minimal spanning tree?*

Of course, it's random. But Frieze showed that as n → ∞, it converges to this number:

ζ(3) = 1/1³ + 1/2³ + 1/3³ + ...

More precisely, for any ε > 0, the probability that this total length differs from ζ(3) by more than ε approaches zero as n → ∞,

This number ζ(3) is called

**Apéry's constant**because Apéry proved what everyone had suspected all along: it's irrational.

I find this fact to be a wonderfully fundamental appearance of Apery’s constant. It was proved by Frieze in 1983, and he published it here:

• Alan M. Frieze, On the value of a random minimum spanning tree problem,

*Discrete Applied Mathematics*

**10**(1985), 47–56. Available for free at http://www.sciencedirect.com/science/article/pii/0166218X85900587

Apery’s constant also shows up when you compute how the electron's

**gyromagnetic ratio**using quantum electrodynamics: an electron is a little magnet, and the gyromagnetic ratio says how strong this magnet is. But the answer to this problem is complicated: it's the sum of infinitely many terms, and Apery’s constant shows up in the 2nd and 3rd terms. So I find this less thrilling, since it's less clean... and also less surprising, perhaps because I understand it a bit better.

Here's another really nice way that Apery’s constant shows up. It's the reciprocal of the probability that 3 positive integers chosen at random are relatively prime!

Now, "choosing a positive integer at random" doesn't really make sense. So here's what you do. For each n, compute the probability that 3 positive integers less than n, chosen uniformly at random, are relatively prime. Then take the limit as n → ∞. Voilà: you get 1/ζ(3).

https://en.wikipedia.org/wiki/Apery's_constant

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[FRENCH] Comment coder votre première application

**voice**avec**Amazon Alexa**.Add a comment...

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**The Appetizer #1: How to launch your idea and get your first signups**

Watch it watch it -

Like it Like it -

**Subscribe Subscribe**:)

That would be so great for us!

(be sure to check the "entr'acte" and "behind the scenes" for more fun)

Got inspired by +Foundr Magazine podcast , +David Cancel / +Dave Gerhardt Seeking Wisdom podcast, and +Steli Efti / +Hiten Shah 's Startup Chat.

Soon on iTunes (waiting for the podcast to be approved)

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Google+ UX has become a mess ....

See what this person is asking on an [EN] community about authorship.

... and to be honest I also crossposted things on the wrong channels without knowing.

See what this person is asking on an [EN] community about authorship.

... and to be honest I also crossposted things on the wrong channels without knowing.

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**The story behind "Track our Startup"**

Have you ever planned and record a video for an international audience about your brand? Damn, it's so hard. I share the reasons that led me to do so anyway.

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**How to deliver your content upgrades for free on Wordpress**

I have been looking around for a while before finding the good setup that allows me to collect emails and deliver content upgrades automatically.

Most of the solutions were costly.

Instead, I managed to find something that fits my need for free.

#wordpress #contentMarketing #contentUpgrade

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**Avoid Social Fatigue**

Do you post on social media

**too much**? It's hard to know of course, people won't tell you, they will just unfollow you. So, think about this, and try to avoid to flood your followers with too many updates.

http://blog.elokenz.com/content-marketing/5-tips-avoid-social-fatigue-social-media-followers

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