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pan xhorn (南风)
Works at 自宅
Attended 四川大学
Lives in 北京
432 followers|96,970 views
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pan xhorn

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哈哈,这个二货
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Cute Dog......
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pan xhorn

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lol
 
谁说后轮永远跑不过前轮的?
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pan xhorn

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what is the gray icons mean? +Google+ 
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Anthony Bueno's profile photopan xhorn's profile photolaohu Ai's profile photo
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啊啊啊~~~撸主滴gmail也灰啦?!这个得握握爪儿咩~
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pan xhorn

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wow
 
Have a Wonderful Night

Amazing photo by +Michael Shainblum 

#photography  
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pan xhorn

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wow
 
Pascal's triangle and the number e

Pascal's triangle is a triangular array of integers, the first few rows of which are shown in the picture. Apart from the flanking strips of 1s, each entry is the sum of the two entries above it. There are many well known patterns among the entries of Pascal's triangle. Two of these patterns are (a) that the sum of the entries in the n-th row is equal to 2^n, and (b) that the alternating sum of entries in the n-th row is equal to 0. For example, if n = 4, this means (a) that 1+4+6+4+1 = 2^4 = 16, and (b) that 1-4+6-4+1 = 0.

A less studied sequence associated with Pascal's triangle is the product of the entries in each row. This sequence, which appears as A001142 in The On-Line Encyclopedia of Integer Sequences (http://oeis.org/A001142) begins 
1, 1, 2, 9, 96, 2500, 162000, 26471025, ...
Let us denote the entries of this sequence by p(1), p(2), p(3), and so on. The remarkable property of the sequence, illustrated in the picture, is that as n becomes large, the value of p(n-1)p(n+1)/(p(n)^2) converges, albeit slowly, to the number e. The number e, which is approximately 2.718281828459045, is a famous irrational number, and is important because it is the base of the natural logarithm.

This post is based on a post by +Richard Elwes, which you can find here (https://plus.google.com/114216686796425894192/posts/EvZyEiKRJtn). The result itself is due to +Harlan Brothers. +Alexander Bogomolny has written up a nice proof of the result here (http://www.cut-the-knot.org/arithmetic/algebra/HarlanBrothers.shtml).

#mathematics
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Have him in circles
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pan xhorn

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Might be handy for some of you: iptables mitigation (using u32 matching) for #heartbleed; logs then drops all TLS heartbeat handshakes.

# Log rules
iptables -t filter -A INPUT -p tcp --dport 443 -m u32 --u32 "52=0x18030000:0x1803FFFF" -j LOG --log-prefix "BLOCKED: HEARTBEAT"

# Block rules
iptables -t filter -A INPUT -p tcp --dport 443 -m u32 --u32 "52=0x18030000:0x1803FFFF" -j DROP

Source: http://www.securityfocus.com/archive/1/531779/30/0/threaded
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pan xhorn

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不跪会死啊。。。
哀其不幸,怒其不争
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那时候可能真的会死
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pan xhorn

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分享给你Nachtblut的单曲《Antik》,来网易云音乐: http://163.fm/6e5PGQO  和我一起听吧~  #TEST
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pan xhorn

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emacs 怎么你了。。。
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哈哈!!!
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pan xhorn

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神同步啊
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I Officially Dub This
The #likeaboss  workout.

#gif   #funnygifs  
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Have him in circles
432 people
Scott Maxwell's profile photo
博文频道's profile photo
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IT
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linux python js
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  • 自宅
    present
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北京
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Introduction
死理性派,linux, emacs user,python and qt programmer,learning functional programming
Education
  • 四川大学
    2003 - 2013
  • 中国石油大学
    2009 - 2012
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Male
Other names
xhorn, pronghorn, 南风