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Anil Das
Works at Google
Attended Stanford University
Lived in Cupetino, CA
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Anil Das

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While India makes strides in moving toward a power surplus, pollution is worsening and access to electricity remains a distant promise for millions
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At 80, Wanda Witter was dismissed as mentally ill as she fought with Social Security over the money she insisted she was due. She was right.
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Home sales in the Bay Area were down 13.5 percent in July compared to the same month in 2015.
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Dmitry, I think conditions are not ripe for a pop. More of a slowdown or slow deflation.
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Take the quiz.

I got Clinton and Johnson tied for best match, which unsurprisingly is not surprising.

Since I'm in Cali, probably gonna go with Johnson.
iSideWith shows which political parties, candidates, and ballot initiatives you should vote for based on your stances to the most important political issues of 2016.
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Apparently the right hate it a lot and use it as one of the reasons to homeschool instead.
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Excellent essay.
No, English isn’t uniquely vibrant or mighty or adaptable. But it really is weirder than pretty much every other language
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Surrogate mothers in the Indian city of Chennai tell the BBC about the emotional bonds they developed with the babies they carried in their wombs for nine months.
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France, wtf happened to liberté, you morons?
A woman is forced to strip off in Nice by French police officers armed with pepper spray and batons. In nearby Cannes three armed officers pointed a pepper spray canister in a woman's face.
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I think we should ban men from wearing speedos cuz that shit is just offensive.
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Anil Das
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Yu Jianchun - self-taught math whiz

Henan is one of the poorer provinces of China.  But there are beautiful mountains in the county of Xinxian.   That's where Yu Jianchun grew up.  Until recently he was a package delivery worker.   He says he barely knows calculus.  But he's been working on number theory.  It took him 8 years to get anyone to pay attention to his discoveries.  But recently he was invited to give a talk at Zhejiang University!

Yu is modest:

"I'm slow-witted.  I need to spend far more time studying math problems than others. Although I am sensitive to numbers, I barely have any knowledge about calculus or geometry."

But he's made some discoveries about Carmichael numbers.  I won't define those, but they're pseudoprimes: they pass a test for being prime that Fermat invented, but they're not actually prime.

What did Yu Jianchun actually discover, and how impressive is it?  Unfortunately I haven't been able to find out!  Can you help? 

An article in China Topix says:

Yu Jianchun developed five formulas for the Carmichael numbers, which are pseudo-prime numbers that occur as positive integers some 255 times per 100 million. He's also developed an alternative method to verify Carmichael numbers.

"I made my discoveries through intuition," said Yu. "I would write down what I thought when inspirations struck about the Carmichael. I have hard work and make a hard living, but I insist on my studies."

Yu sent his solutions to Dr. Cai Tianxin, a math professor at Zhejiang University, along with solutions to four other problems. He later presented his solutions to the public at a graduate student seminar at the invitation of Cai. Yu's solution to complex math problem has also amazed Chinese academics.

Yu said it took over eight years of writing letters to prominent Chinese mathematicians to get any recognition for his talent.
 
"It was a very imaginative solution," said Cai.

"He has never received any systematic training in number theory nor taken advanced math classes. All he has is an instinct and an extreme sensitivity to numbers."

 In late June, China Daily told a slightly different story, with some overlap but also this:

Yu was a migrant worker in many places, and everywhere he went, he would visit the math professors at the local university, hoping to get confirmation of his formulas.

Yu said he spent eight years developing the Carmichael formulas. He has reached out to academics through emails. Cai was the first to respond.

Cai found a formula proposed by Yu to be a more efficient way of identifying Carmichael numbers and invited him to share his thinking at the university with faculty members and doctoral and postdoctoral students in a class on June 13.

Six professors and advanced students in Zhejiang University's math department listened to Yu's lecture. Some of the experts considered Yu's idea to be a "novelty", while some said "his results have a certain depth".

Cai decided to include Yu's formula with his latest work in English, and he gave Yu a book to help the logistics worker in further study.

It seems he is no Ramanujan, but still a remarkable person who could use some help.  He may finally be getting it.  CNN writes:

After local and national media reported on his findings, Yu has become a local celebrity. A company that manufactures silk products has offered him a less labor-intensive job to give him more time to study math.

Yu had never heard of the movie "Good Will Hunting," but says he's curious to see it.

The 1997 drama, which stars Matt Damon and Robin Williams, tells the fictional story of a maths genius who works as a janitor at the Massachusetts Institute of Technology.

Slightly overwhelmed by his sudden fame, Yu said he is nevertheless grateful for the new opportunities that hopefully lie ahead.

However, at age 33 and still single, he says his primary concern is to get married.

People on MathOverflow are trying to figure out, from tiny clues, what Yu has done:

http://mathoverflow.net/questions/244751/what-did-yu-jianchun-discover-about-carmichael-numbers

The China Topix article is here:

http://www.chinatopix.com/articles/95664/20160718/slow-witted-chinese-math-genius-amazes-carmichael-numbers-formulas.htm

The China Daily article is here:

http://www.chinadaily.com.cn/china/2016-06/23/content_25813818.htm

The CNN article is here:

http://edition.cnn.com/2016/07/17/asia/china-migrant-worker-good-will-hunting/index.html

To learn about Carmichael numbers, go here:

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

#mathematics  
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OK, I realize it's edited and cherrypicked and all that, but is still quite funny.
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"he's surrounding himself with advisers" - locked portas, homes.
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That's cool! Good for her.
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Millions in economic damage, all because some people cheered Usain Bolt a little too hard.
Officials said there was no evidence that a report of gunfire at J.F.K. on Sunday night was a deliberate hoax. What followed, they said, was a sign of the times.
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nah, i'd say just the right amount.
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SW Engineer.
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  • Google
    2009 - present
  • Silicon Graphics, Inc.
    1997 - 2009
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  • Stanford University
    MSCS, 2009 - 2015
  • Indian Institute of Technology Madras
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