## Profile

Devaraj NS
Attended GBHS, Attur
Lives in Chennai
1,533 followers|638,993 views

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How Project InnerTube Helped Pull YouTube Out of the Gutter﻿
Three years ago, YouTube had a big problem. People were watching YouTube videos on blogs, news sites and social media—everywhere but YouTube. As a result, the site’s 1 billion monthly viewers were only bringing the company \$4 billion in revenue, less than what Netflix was skimming off just 50 million subscribers.
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The Vortex is a new kind of wind turbine being developed without any blades.﻿
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Ha ha ha﻿

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This DIY Raspberry Pi Laptop Is Perfect For Your Weekend Machinations﻿
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என்னோட Redmi1S போனுக்கே நான் மவுஸ் அட்டாச் பண்ணி டய்ப் அடிக்கிறேனாக்கும் :-)))﻿
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Why is this true?

The spooky-smart mathematician Srinivasa Ramanujan came up with this formula around 1913.  Why is it true?

I don't know, let's see...

In 1735, a young fellow named Euler stunned the world by cracking a famous puzzle that had been unsolved for almost a century: the Basel problem.  The problem was to sum the reciprocals of perfect squares:

1/1² + 1/2² + 1/3² + 1/4² + 1/5² ... = ???

Euler showed that the answer was π²/6:

1/1² + 1/2² + 1/3² + 1/4² + 1/5² ... = π²/6

He also showed you could rewrite this sum as a product over primes:

1/1² + 1/2² + 1/3² + 1/4² + 1/5² ... =

(2²/(2² - 1)) (3²/(3² - 1)) (5²/(5² - 1)) (7²/(7² - 1)) ...

That's actually the easy part: it's a cute trick called the Euler product formula.

So we know

(2²/(2² - 1)) (3²/(3² - 1)) (5²/(5² - 1)) (7²/(7² - 1)) ... = π²/6

If you think about it, Ramanujan's formula is saying that

(2²/(2² + 1)) (3²/(3² + 1)) (5²/(5² + 1)) (7²/(7² + 1)) ...

is 2/5 as big.  So, proving it is the same as showing

(2²/(2² + 1)) (3²/(3² + 1)) (5²/(5² + 1)) (7²/(7² + 1)) ... = π²/15

Maybe the next step is to use the same idea as the Euler product formula.  I think this gives

(2²/(2² + 1)) (3²/(3² + 1)) (5²/(5² + 1)) (7²/(7² + 1)) ... =
1/1² - 1/2² - 1/3² + 1/4² + 1/5² - 1/6² + 1/7² + ...

where the signs at right follow a fancy pattern: we get 1/n² whenever n is the product of an even number of primes, and -1/n² when n is the product of an odd number of primes.  For example, 4 = 2 x 2 is the product of an even number of primes, so we get 1/4².

So I'm left wanting to know why this strange sum

1/1² - 1/2² - 1/3² + 1/4² + 1/5² - 1/6² + 1/7² + ...

equals π²/15.  Ramanujan, dead since 1920, is still messing with my mind!

The formula is supposed to be in here:

• Srinivasa Ramanujan, Modular equations and approximations to π, Quart. J. Pure. Appl. Math. 45 (1913-1914), 350-372.  Also available at ://ramanujan.sirinudi.org/Volumes/published/ram06.pdf.

But I don't see it!

Here you can see how Euler solved the Basel problem:

https://en.wikipedia.org/wiki/Basel_problem

It's a great example of his brilliant tactics, many of which were far from rigorous by today's standards... but can be made rigorous.

#mathematics   ﻿
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He was frickin' amazing﻿

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Mobile phone companies should see data as an opportunity, not crisis, firm says
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There's an Android bot peeing on an Apple logo on Google Maps﻿
An image of an Android mascot peeing on an Apple logo has been discovered on Google Maps.
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RoboRoach

You can now make your own cyborg roach for just \$100.   Just buy this kit developed by the company Backyard Brains:

Are you a teacher or parent that wants to teach a student about advanced neurotechnologies? You are in luck! After 3 long years of R&D, the RoboRoach is now ready for its grand release! We are excited to announce the world's first commercially available cyborg! With our RoboRoach you can briefly wirelessly control the left/right movement of a cockroach by microstimulation of the antenna nerves. The RoboRoach is a great way to learn about neural microstimulation, learning, and electronics!

We are recently ran a successfully-funded kickstarter campaign to fund the release of our new RoboRoach! The hardware and firmware development are complete and we are now shipping!

Product Details

The RoboRoach "backpack" weighs 4.4 grams with the battery, and each battery will last over a month! Following a brief surgery you perform on the cockroach to attach the silver electrodes to the antenna, you can attach the backpack to the roach and control its movement for a few minutes before the cockroach adapts. When you return the cockroach to its cage for ~20 minutes, he "forgets" and the stimulation works again. Once you receive your RoboRoach in the mail, follow our online surgery instructions and videos and you will soon be on your way to becoming an expert in neural interfaces. After about 2-7 days, the stimulation stops working altogether, so you can clip the wires and retire the cockroach to your breeder colony to spend the rest of its days making more cockroaches for you and eating your lettuce.

Technical Specs

1x Free iOS or Android 4.3+ application for remote control
1x Bluetooth Roboroach backpack control unit
1x 1632 RoboRoach Battery
3x Electrode Sets (to implant 3 Roaches)

View our RoboRoach Ethics Statement

Backyard Brains has developed ethical guidelines for all our products. You can read more in our statement regarding our use of insect for experiments at:

http://ethics.backyardbrains.com

I feel ethical qualms about taking away the autonomy of an animal this way, and their ethics statement doesn't really address that.  This is the closest they come:

Criticism: Modifying a living creature to make a toy is wrong.

The RoboRoach circuit is not a toy. This new bluetooth version is a powerful low-cost tool for studying neural circuits, allowing for students to make discoveries. High school students in New York, for example, have discovered random stimulation causes much slower adaptation times. We have scientist and high school educator colleagues who are mentoring students in novel behavioral experiments using the RoboRoach circuit. Some highlights will be posted on our website soon.

By focusing on the question of whether the RoboRoach is a "toy", they dodge the harder question of when it's okay to override the nervous system of an animal and make it do what you want.  Perhaps feeling a bit nervous about this, some of the cyborg roach developers say they want to use it as a "rescue robot" that can crawl around and hear people trapped under collapsed buildings.  I think most people would say this is okay, at least if it actually works.

For a critical view on the ethics, see:

http://www.livescience.com/40821-roboroach-is-inhumane.html

For more on how to actually make a RoboRoach, go here:

http://www.popsci.com/science/article/2012-12/how-build-your-own-cockroach-cyborg﻿
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OK, here's the basics of fielding in cricket.   Yes, this will be on the test.﻿
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People
In his circles
841 people
Have him in circles
1,533 people
Work
Occupation
Technologist
Skills
ActionScript, Flex, Java, JavaScript, Objective-C, Hibernate, Spring, Oracle, Unity3D
Places
Currently
Chennai
Previously
Chennai - Attur - Trichy - Karur - Chennai - Hyderabad - Mysore - Bangalore - Pune - Coimbatore - Pondicherry
Contributor to
Story
Tagline
Senior Architect, VisualBI
Introduction
SAP BI Architect,Flex Architect, iOS Coder, Unity 3D Developer
Bragging rights
Have a kid (Guru)
Education
• GBHS, Attur
Maths, 1990 - 1997
• St. Joseph's Trichy
Physics, 1997 - 2000
• Bharathidasan University
Computer Applications, 2000 - 2003
Basic Information
Gender
Male
Birthday
February 9
Relationship
Married
Other names
Devaraj NS's +1's are the things they like, agree with, or want to recommend.
 What's new in Design Studio 1.5 SDKscn.sap.comLike last time, I'll give the community a brief overview of the new and improved topics in the SDK for Design Studio 1.5. While in 1.4 there
 ASUG SAPPHIRENOW Speaker Profile Gopal Krishnamurthy - Design Studio and...scn.sap.comI am pleased to introduce ASUG Annual Conference speaker Gopal Krishnmurthy Gopal's session is BI624 "Customizing Design Studio Applications
 Design Studio SDK (1.3/1.4) - Opensource SCN Maps (Part 1)scn.sap.com(I say this is 'Part 1' because I'm not done with this but I promised myself I'd release what I had before end of 2014 and it's Dec 31st, so
 10 Object Oriented Design Principles Java Programmer should knowjavarevisited.blogspot.comCollection of 10 OOPS and SOLID design principles which are essential for Java programmer to write flexible, maintainable and quality code.
 ஆங்கில வழிக் கல்வி கூடாதா..?anindianvoice.blogspot.comஆங்கில வழிக் கல்விக்கு எதிர்ப்பு தெரிவித்திருக்கும் கருணாநிதி தமிழ் வழி மூலமே குழந்தைகளுக்கு கல்வி கற்பிக்கப்பட வேண்டும் என்று வலியுறுத்தியி
 SAP Lumira – Geek Tweaksscn.sap.comI’ve been playing around with Lumira for a while now and tried some geeky tweaks on it. Here are some of which I am sharing through this pos