"중심이항계수 (central binomial coefficient)"의 두 판 사이의 차이

수학노트
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(사용자 2명의 중간 판 67개는 보이지 않습니다)
1번째 줄: 1번째 줄:
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==개요==
  
 
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*  다음과 같은 [[이항계수와 조합|이항계수]]로 정의
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:<math>{2n \choose n}=\frac{(2n)!}{(n!)^2},\quad n\in \mathbb{Z}_{\geq 0}</math>
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* 1, 2, 6, 20, 70, 252, 924, 3432, 12870, 48620, 184756,...
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* <math>n\geq 1</math>일 때 짝수
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*  동전을 2n 번 던질때, 앞뒷면이 각각 n 번 나올 확률을 표현할 때 등장
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*  아페리가 [[Ζ(3)는 무리수이다(아페리의 정리)]]를 증명하는데 활용됨
  
 
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==중심이항계수의 근사식==
  
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* http://planetmath.org/encyclopedia/AsymptoticsOfCentralBinomialCoefficient.html
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* [http://bomber0.byus.net/index.php/2008/07/12/687 드무아브르의 중심극한정리(iii) : 숫자 파이와 동전던지기] 피타고라스의 창, 2008-7-12
  
 
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동전을 2n 번 던질때, 앞뒷면이 각각 n 번 나올 확률은 수학적으로 다음과 같다.
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:<math>\frac{1}{2^{2n}}{2n\choose n} = \frac{1}{2^{2n}}{{(2n)!} \over {n!n!}}</math>
  
 
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한편 [[월리스 곱 (Wallis product formula)|월리스의 공식]]에서 일반항은 다음과 같은데,
  
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:<math>p_n ={1\over{2n+1}}\prod_{k=1}^{n} \frac{(2k)^4 }{((2k)(2k-1))^2}={1\over{2n+1}}\cdot {{2^{4n}\,(n!)^4}\over {((2n)!)^2}}</math>
  
 
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따라서
  
* Math Overflow http://mathoverflow.net/search?q=
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:<math>p_n ={1\over{2n+1}}\cdot {{2^{4n}\,(n!)^4}\over {((2n)!)^2}} \approx {1\over{2n}}\cdot {{2^{4n}\,(n!)^4}\over {((2n)!)^2}}</math>
* 네이버 지식인 http://kin.search.naver.com/search.naver?where=kin_qna&query=
 
  
 
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이는 월리스의 공식을 다음과 같은 방식으로도 쓸 수 있다는 것을 말해준다.
  
 
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:<math>\frac{\pi}{2} =\lim_{n \to \infty} {1\over{2n}}\cdot {{2^{4n}\,(n!)^4}\over {((2n)!)^2}}</math> 그리고 이는 다음을 말해준다.
  
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:<math>\frac{1}{2^{2n}}{{(2n)!} \over {n!n!}}= \frac{1}{2^{2n}}{2n\choose n} \approx \frac{1}{\sqrt{\pi n}}</math>
  
 
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* http://www.google.com/search?hl=en&tbs=tl:1&q=
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==멱급수와 중심이항계수==
* [[수학사연표 (역사)|수학사연표]]
 
*  
 
  
 
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* [[이항급수와 이항정리]]
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:<math>\frac{1}{\sqrt{1-4z}}=\sum_{n=0}^{\infty} {{2n}\choose {n}} z^n</math>
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* [[역삼각함수]]
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:<math>2(\arcsin x)^2=\sum_{n=1}^{\infty}\frac{(2x)^{2n}}{n^2\binom{2n}{n}}</math>
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:<math>\frac{2x \arcsin x}{\sqrt{1-x^2}}=\sum_{n=1}^{\infty}\frac{(2x)^{2n}}{n\binom{2n}{n}}</math>
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:<math>\frac{4 \left(\sqrt{4-z}+\sqrt{z} \sin ^{-1}\left(\frac{\sqrt{z}}{2}\right)\right)}{(4-z)^{3/2}}=\sum_{n=0}^{\infty}\frac{z^n}{ {{2n}\choose {n}}}</math>
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* [[카탈란 수열(Catalan numbers)]] 의 생성함수
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:<math>G(x)= \frac{1-\sqrt{1-4x}}{2x}=\sum_{n=0}^{\infty}\frac{1}{n+1}{2n\choose n}x^n</math>
  
 
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== 중심이항계수가 나타나는 급수==
  
 
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* '''[Lehmer1985]''' 참조
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;정리
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:<math>\sum_{n=1}^{\infty}\frac{1}{n\binom{2n}{n}}=\frac{\pi\sqrt{3}}{9}</math>
  
 
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;증명
  
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:<math>\frac{2x \arcsin x}{\sqrt{1-x^2}}=\sum_{n=1}^{\infty}\frac{(2x)^{2n}}{n\binom{2n}{n}}</math> 에서 <math>x=\frac{1}{2}</math>인 경우, <math>\sum_{n=1}^{\infty}\frac{1}{n\binom{2n}{n}}=\frac{\pi\sqrt{3}}{9}</math> 를 얻는다. ■
  
 
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;정리
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:<math>\sum_{n=1}^{\infty}\frac{1}{n^{2}\binom{2n}{n}}=\frac{\pi^2}{18}</math>
  
 
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;증명
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:<math>2(\arcsin x)^2=\sum_{n=1}^{\infty}\frac{(2x)^{2n}}{n^2\binom{2n}{n}}</math>에서 <math>x=\frac{1}{2}</math>인 경우, <math>\sum_{n=1}^{\infty}\frac{1}{n^{2}\binom{2n}{n}}=\frac{\pi^2}{18}</math>를 얻는다.■
  
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;정리
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:<math>\sum_{n=1}^\infty \frac{1}{n^3\binom{2n}{n}}=\frac{2\pi}{3}\operatorname{Cl}_ 2(\frac{\pi}{3})-\frac{4}{3}\zeta(3)=\pi\operatorname{Cl}_ 2(\frac{2\pi}{3})-\frac{4}{3}\zeta(3)=\frac{\pi\sqrt{3}}{18}(\psi^{(1)}(\frac{1}{3})-\psi^{(1)}(\frac{2}{3}))-\frac{4}{3}\zeta(3)</math>
  
* 단어사전 http://www.google.com/dictionary?langpair=en|ko&q=
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여기서 <math>\operatorname{Cl}_ 2(\theta)</math> 는 [[로바체프스키 함수|로바체프스키와 클라우센 함수]], <math>\psi^{(1)}</math>는 [[트리감마 함수(trigamma function)]].
* 발음사전 http://www.forvo.com/search/
 
* [http://mathnet.kaist.ac.kr/mathnet/math_list.php?mode=list&ftype=&fstr= 대한수학회 수학 학술 용어집]<br>
 
** http://mathnet.kaist.ac.kr/mathnet/math_list.php?mode=list&ftype=eng_term&fstr=
 
* [http://www.nktech.net/science/term/term_l.jsp?l_mode=cate&s_code_cd=MA 남·북한수학용어비교]
 
* [http://kms.or.kr/home/kor/board/bulletin_list_subject.asp?bulletinid=%7BD6048897-56F9-43D7-8BB6-50B362D1243A%7D&boardname=%BC%F6%C7%D0%BF%EB%BE%EE%C5%E4%B7%D0%B9%E6&globalmenu=7&localmenu=4 대한수학회 수학용어한글화 게시판]
 
  
 
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;증명
  
 
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[http://www.research.att.com/%7Enjas/sequences/A145438 http://www.research.att.com/~njas/sequences/A145438]
  
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:<math>\sum_{n=1}^\infty \frac{1}{n^3\binom{2n}{n}}=4\int_{0}^{\frac{1}{2}}(\arcsin x)^2\frac{dx}{x}=-2\int_{0}^{\pi/3}x\log(2\sin \frac{x}{2})\,dx</math>
  
* http://ko.wikipedia.org/wiki/
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[http://www.wolframalpha.com/input/?i=integrate+%28arcsin+x%29%5E2/x+dx+from+x%3D0+to+1/2 http://www.wolframalpha.com/input/?i=integrate+(arcsin+x)^2/x+dx+from+x%3D0+to+1/2]
* http://en.wikipedia.org/wiki/
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* http://www.wolframalpha.com/input/?i=
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* [http://dlmf.nist.gov/ NIST Digital Library of Mathematical Functions]
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* [http://www.research.att.com/~njas/sequences/index.html The On-Line Encyclopedia of Integer Sequences]<br>
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좌변 http://www.wolframalpha.com/input/?i=sum+1%2F%28m%5E3*binom%282m%2Cm%29%29+from+1+to+infinity
** http://www.research.att.com/~njas/sequences/?q=
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우변 [http://www.wolframalpha.com/input/?i=-4*zeta%283%29/3%2Bpi*sqrt%283%29*%28trigamma%281/3%29-trigamma%282/3%29%29/18 http://www.wolframalpha.com/input/?i=-4*zeta(3)/3%2Bpi*sqrt(3)*(trigamma(1/3)-trigamma(2/3))/18] ■
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;정리(Comtet의 공식)
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:<math>\sum_{n=1}^\infty \frac{1}{n^4\binom{2n}{n}}=\frac{17\pi^4}{3240}</math>
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증명은 [[ζ(4)와 중심이항계수]]을 참고
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==원주율의 유리수 근사와 중심이항계수==
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<math>\sum_{n=1}^{\infty}\frac{2^{n}}{\binom{2n}{n}}=\frac{\pi}{2}+1</math>
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<math>\sum_{n=1}^{\infty}\frac{n2^{n}}{\binom{2n}{n}}=\pi+3</math>
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<math>\sum_{n=1}^{\infty}\frac{n^2 2^{n}}{\binom{2n}{n}}=\frac{7\pi}{2}+11</math>
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<math>\sum_{n=1}^{\infty}\frac{n^3 2^{n}}{\binom{2n}{n}}=\frac{35\pi}{2}+55</math>
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<math>\sum_{n=1}^{\infty}\frac{n^4 2^{n}}{\binom{2n}{n}}=113\pi+355</math>
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<math>\sum_{n=1}^{\infty}\frac{n^{5} 2^{n}}{\binom{2n}{n}} = \frac{1787\pi}{2}+2807</math>
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<math>\sum_{n=1}^{\infty}\frac{n^{6} 2^{n}}{\binom{2n}{n}} = \frac{16717\pi}{2}+26259</math>
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<math>\sum_{n=1}^{\infty}\frac{n^{10} 2^{n}}{\binom{2n}{n}}=229093376\pi+719718067</math>
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http://www.wolframalpha.com/input/?i=sum+1%2F%28m%5E3*binom%282m%2Cm%29%29+from+1+to+infinity
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[http://www.wolframalpha.com/input/?i=sum+m%5E6*2%5Em/%28binom%282m,m%29%29+from+1+to+infinity http://www.wolframalpha.com/input/?i=sum+m^6*2^m/(binom(2m,m))+from+1+to+infinity]
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일반적으로 <math>k\in\mathbb{N}</math>에 대하여,
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<math>\sum_{n=1}^{\infty}\frac{n^{k} 2^{n}}{\binom{2n}{n}}=a\pi+b</math> , (a와 b는 유리수) 형태로 주어진다. '''[Lehmer1985] '''참조
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==리만제타함수==
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<math>\zeta(2)=3\sum_{n=1}^{\infty}\frac{1}{n^{2}\binom{2n}{n}}</math>
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<math>\zeta(3) = \frac{5}{2} \sum_{n=1}^\infty \frac{(-1)^{n-1}}{n^3\binom{2n}{n}}</math>
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<math>\zeta(4) = \frac{36}{17} \sum_{n=1}^\infty \frac{1}{n^4\binom{2n}{n}}</math>
  
 
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==메모==
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* Kalmykov, M. Yu., and O. Veretin. 2000. “Single-Scale Diagrams and Multiple Binomial Sums.” Physics Letters B 483 (1–3) (June 15): 315–323. doi:10.1016/S0370-2693(00)00574-8.
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* http://math.stackexchange.com/questions/153504/the-fermat-prime-257-and-binomial-sum-sum-n-0-infty-frac-1n-binom-8
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* http://mathoverflow.net/questions/98897/a-coincidence-concerning-fermat-primes-binomial-sums-and-eta-quotients
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* http://tpiezas.wordpress.com/2012/06/03/fermat-primes-and-binomial-sums/
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* http://www1.au.edu.tw/ox_view/edu/tojms/j_paper/Full_text/Vol-25/No-2/25%282 %297-2%28141-151%29.pdf
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*'''[Lehmer1985]'''에는 다음과 같은 공식이 나오지만, 잘못된 것이다.
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:<math>\sum_{n=1}^\infty \frac{1}{n^3\binom{2n}{n}}=-\frac{\zeta(3)}{3}-\frac{\pi\sqrt{3}}{72}(\psi^{(1)}(\frac{1}{3})-\psi^{(1)}(\frac{2}{3}))</math>
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바른 공식은 다음과 같다.
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:<math>\sum_{n=1}^\infty \frac{1}{n^3\binom{2n}{n}}=\frac{\pi\sqrt{3}}{18}(\psi^{(1)}(\frac{1}{3})-\psi^{(1)}(\frac{2}{3}))-\frac{4}{3}\zeta(3)</math>
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여기서 <math>\psi^{(1)}</math>는 트리감마(trigamma)함수. [[트리감마 함수(trigamma function)]]항목 참조
  
* [http://escholarship.org/uc/item/7wd7j9nz Experimental Determination of Apéry-like Identities&nbsp;for ζ(2n + 2)]<br>
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** David H. Bailey, Jonathan M. Borwein, and David M. Bradley
 
* [http://arxiv.org/abs/hep-th/0004153 Central Binomial Sums, Multiple Clausen Values and Zeta Values]<br>
 
** [http://arxiv.org/abs/hep-th/0004153 ]J. M. Borwein, D. J. Broadhurst, J. Kamnitzer, 2000
 
* http://www.jstor.org/action/doBasicSearch?Query=
 
* http://www.ams.org/mathscinet
 
* http://dx.doi.org/
 
  
 
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==관련된 항목들==
  
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* [[카탈란 수열(Catalan numbers)]]
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* [[Ζ(3)는 무리수이다(아페리의 정리)]]
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* [[폴리로그 함수(polylogarithm)]]
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* [[이항급수와 이항정리]]
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* [[정규분포와 그 확률밀도함수]]
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* [[중심이항계수가 등장하는 어떤 급수에 대한 문제]]
  
*  도서내검색<br>
 
** http://books.google.com/books?q=
 
** http://book.daum.net/search/contentSearch.do?query=
 
*  도서검색<br>
 
** http://books.google.com/books?q=
 
** http://book.daum.net/search/mainSearch.do?query=
 
** http://book.daum.net/search/mainSearch.do?query=
 
  
 
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==매스매티카 파일 및 계산 리소스==
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* https://docs.google.com/file/d/0B8XXo8Tve1cxSDhxWm9WQnZpV3c/edit
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* http://oeis.org/A000984
  
 
 
  
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==사전 형태의 자료==
  
* 네이버 뉴스 검색 (키워드 수정)<br>
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* http://ko.wikipedia.org/wiki/
** http://news.search.naver.com/search.naver?where=news&x=0&y=0&sm=tab_hty&query=
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* http://en.wikipedia.org/wiki/Central_binomial_coefficient
** http://news.search.naver.com/search.naver?where=news&x=0&y=0&sm=tab_hty&query=
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* [http://mathworld.wolfram.com/CentralBinomialCoefficient.html http://math world.wolfram.com/CentralBinomialCoefficient.html]
** http://news.search.naver.com/search.naver?where=news&x=0&y=0&sm=tab_hty&query=
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* http://mathworld.wolfram.com/BinomialSums.html
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* http://planetmath.org/GeneratingFunctionForTheReciprocalCentralBinomialCoefficients.html
  
 
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==관련논문==
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* Bruner, Marie-Louise. ‘Central Binomial Coefficients Also Count (2431,4231,1432,4132)-Avoiders’. arXiv:1505.04929 Null, 19 May 2015. http://arxiv.org/abs/1505.04929.
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* Renzo Sprugnoli, Sum of reciprocals of the Central Binomial Coefficients, Integers: electronic journal of combinatorial number theory, 6 (2006) A27, 1-18
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* Bailey, David H., Jonathan M. Borwein, and David M. Bradley. 2005. “Experimental Determination of Apery-Like Identities for Zeta(2n+2).” Lawrence Berkeley National Laboratory (May 11). http://escholarship.org/uc/item/7wd7j9nz.
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* Borwein, Jonathan M., and Roland Girgensohn. 2005. “Evaluations of Binomial Series.” Aequationes Mathematicae 70 (1-2) (September 1): 25–36. doi:10.1007/s00010-005-2774-x.
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* Borwein, J. M., D. J. Broadhurst, and J. Kamnitzer. 2000. “Central Binomial Sums, Multiple Clausen Values and Zeta Values.” arXiv:hep-th/0004153 (April 22). http://arxiv.org/abs/hep-th/0004153.
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* '''[Lehmer1985]''' Lehmer, D. H. 1985. “Interesting Series Involving the Central Binomial Coefficient.” The American Mathematical Monthly 92 (7) (August): 449. doi:10.2307/2322496.
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* Zucker, I. J. 1985. “On the Series <math>\sum_{k=1}^{\infty}\binom{2n}{n}^{-1}k^{−n}</math> and Related Sums.” Journal of Number Theory 20 (1) (February): 92–102. doi:10.1016/0022-314X(85)90019-8.
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* A.J. Van der Poorten. Some wonderful formulas ... an introduction to polylogarithms, Queen's papers in Pure and Applied Mathematics, 54 (1979), 269-286
  
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==관련도서==
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* http://books.google.co.kr/books?id=C0HPgWhEssYC
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[[분류:조합수학]]
  
*  구글 블로그 검색<br>
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==메타데이터==
** http://blogsearch.google.com/blogsearch?q=
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===위키데이터===
* [http://navercast.naver.com/science/list 네이버 오늘의과학]
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* ID : [https://www.wikidata.org/wiki/Q1045966 Q1045966]
* [http://math.dongascience.com/ 수학동아]
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===Spacy 패턴 목록===
* [http://www.ams.org/mathmoments/ Mathematical Moments from the AMS]
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* [{'LOWER': 'central'}, {'LOWER': 'binomial'}, {'LEMMA': 'coefficient'}]
* [http://betterexplained.com/ BetterExplained]
 

2021년 2월 17일 (수) 05:00 기준 최신판

개요

\[{2n \choose n}=\frac{(2n)!}{(n!)^2},\quad n\in \mathbb{Z}_{\geq 0}\]

  • 1, 2, 6, 20, 70, 252, 924, 3432, 12870, 48620, 184756,...
  • \(n\geq 1\)일 때 짝수
  • 동전을 2n 번 던질때, 앞뒷면이 각각 n 번 나올 확률을 표현할 때 등장
  • 아페리가 Ζ(3)는 무리수이다(아페리의 정리)를 증명하는데 활용됨


중심이항계수의 근사식

동전을 2n 번 던질때, 앞뒷면이 각각 n 번 나올 확률은 수학적으로 다음과 같다. \[\frac{1}{2^{2n}}{2n\choose n} = \frac{1}{2^{2n}}{{(2n)!} \over {n!n!}}\]

한편 월리스의 공식에서 일반항은 다음과 같은데,

\[p_n ={1\over{2n+1}}\prod_{k=1}^{n} \frac{(2k)^4 }{((2k)(2k-1))^2}={1\over{2n+1}}\cdot {{2^{4n}\,(n!)^4}\over {((2n)!)^2}}\]

따라서

\[p_n ={1\over{2n+1}}\cdot {{2^{4n}\,(n!)^4}\over {((2n)!)^2}} \approx {1\over{2n}}\cdot {{2^{4n}\,(n!)^4}\over {((2n)!)^2}}\]

이는 월리스의 공식을 다음과 같은 방식으로도 쓸 수 있다는 것을 말해준다.

\[\frac{\pi}{2} =\lim_{n \to \infty} {1\over{2n}}\cdot {{2^{4n}\,(n!)^4}\over {((2n)!)^2}}\] 그리고 이는 다음을 말해준다.

\[\frac{1}{2^{2n}}{{(2n)!} \over {n!n!}}= \frac{1}{2^{2n}}{2n\choose n} \approx \frac{1}{\sqrt{\pi n}}\]



멱급수와 중심이항계수

\[\frac{1}{\sqrt{1-4z}}=\sum_{n=0}^{\infty} {{2n}\choose {n}} z^n\]

\[2(\arcsin x)^2=\sum_{n=1}^{\infty}\frac{(2x)^{2n}}{n^2\binom{2n}{n}}\] \[\frac{2x \arcsin x}{\sqrt{1-x^2}}=\sum_{n=1}^{\infty}\frac{(2x)^{2n}}{n\binom{2n}{n}}\] \[\frac{4 \left(\sqrt{4-z}+\sqrt{z} \sin ^{-1}\left(\frac{\sqrt{z}}{2}\right)\right)}{(4-z)^{3/2}}=\sum_{n=0}^{\infty}\frac{z^n}{ {{2n}\choose {n}}}\]

\[G(x)= \frac{1-\sqrt{1-4x}}{2x}=\sum_{n=0}^{\infty}\frac{1}{n+1}{2n\choose n}x^n\]



중심이항계수가 나타나는 급수

  • [Lehmer1985] 참조
정리

\[\sum_{n=1}^{\infty}\frac{1}{n\binom{2n}{n}}=\frac{\pi\sqrt{3}}{9}\]

증명

\[\frac{2x \arcsin x}{\sqrt{1-x^2}}=\sum_{n=1}^{\infty}\frac{(2x)^{2n}}{n\binom{2n}{n}}\] 에서 \(x=\frac{1}{2}\)인 경우, \(\sum_{n=1}^{\infty}\frac{1}{n\binom{2n}{n}}=\frac{\pi\sqrt{3}}{9}\) 를 얻는다. ■

정리

\[\sum_{n=1}^{\infty}\frac{1}{n^{2}\binom{2n}{n}}=\frac{\pi^2}{18}\]

증명

\[2(\arcsin x)^2=\sum_{n=1}^{\infty}\frac{(2x)^{2n}}{n^2\binom{2n}{n}}\]에서 \(x=\frac{1}{2}\)인 경우, \(\sum_{n=1}^{\infty}\frac{1}{n^{2}\binom{2n}{n}}=\frac{\pi^2}{18}\)를 얻는다.■

정리

\[\sum_{n=1}^\infty \frac{1}{n^3\binom{2n}{n}}=\frac{2\pi}{3}\operatorname{Cl}_ 2(\frac{\pi}{3})-\frac{4}{3}\zeta(3)=\pi\operatorname{Cl}_ 2(\frac{2\pi}{3})-\frac{4}{3}\zeta(3)=\frac{\pi\sqrt{3}}{18}(\psi^{(1)}(\frac{1}{3})-\psi^{(1)}(\frac{2}{3}))-\frac{4}{3}\zeta(3)\]

여기서 \(\operatorname{Cl}_ 2(\theta)\) 는 로바체프스키와 클라우센 함수, \(\psi^{(1)}\)는 트리감마 함수(trigamma function).

증명

http://www.research.att.com/~njas/sequences/A145438

\[\sum_{n=1}^\infty \frac{1}{n^3\binom{2n}{n}}=4\int_{0}^{\frac{1}{2}}(\arcsin x)^2\frac{dx}{x}=-2\int_{0}^{\pi/3}x\log(2\sin \frac{x}{2})\,dx\]

http://www.wolframalpha.com/input/?i=integrate+(arcsin+x)^2/x+dx+from+x%3D0+to+1/2


좌변 http://www.wolframalpha.com/input/?i=sum+1%2F%28m%5E3*binom%282m%2Cm%29%29+from+1+to+infinity

우변 http://www.wolframalpha.com/input/?i=-4*zeta(3)/3%2Bpi*sqrt(3)*(trigamma(1/3)-trigamma(2/3))/18


정리(Comtet의 공식)

\[\sum_{n=1}^\infty \frac{1}{n^4\binom{2n}{n}}=\frac{17\pi^4}{3240}\]

증명은 ζ(4)와 중심이항계수을 참고

원주율의 유리수 근사와 중심이항계수

\(\sum_{n=1}^{\infty}\frac{2^{n}}{\binom{2n}{n}}=\frac{\pi}{2}+1\)

\(\sum_{n=1}^{\infty}\frac{n2^{n}}{\binom{2n}{n}}=\pi+3\)

\(\sum_{n=1}^{\infty}\frac{n^2 2^{n}}{\binom{2n}{n}}=\frac{7\pi}{2}+11\)

\(\sum_{n=1}^{\infty}\frac{n^3 2^{n}}{\binom{2n}{n}}=\frac{35\pi}{2}+55\)

\(\sum_{n=1}^{\infty}\frac{n^4 2^{n}}{\binom{2n}{n}}=113\pi+355\)

\(\sum_{n=1}^{\infty}\frac{n^{5} 2^{n}}{\binom{2n}{n}} = \frac{1787\pi}{2}+2807\)

\(\sum_{n=1}^{\infty}\frac{n^{6} 2^{n}}{\binom{2n}{n}} = \frac{16717\pi}{2}+26259\)

\(\sum_{n=1}^{\infty}\frac{n^{10} 2^{n}}{\binom{2n}{n}}=229093376\pi+719718067\)

http://www.wolframalpha.com/input/?i=sum+1%2F%28m%5E3*binom%282m%2Cm%29%29+from+1+to+infinity

http://www.wolframalpha.com/input/?i=sum+m^6*2^m/(binom(2m,m))+from+1+to+infinity

일반적으로 \(k\in\mathbb{N}\)에 대하여,

\(\sum_{n=1}^{\infty}\frac{n^{k} 2^{n}}{\binom{2n}{n}}=a\pi+b\) , (a와 b는 유리수) 형태로 주어진다. [Lehmer1985] 참조


리만제타함수

\(\zeta(2)=3\sum_{n=1}^{\infty}\frac{1}{n^{2}\binom{2n}{n}}\)

\(\zeta(3) = \frac{5}{2} \sum_{n=1}^\infty \frac{(-1)^{n-1}}{n^3\binom{2n}{n}}\)

\(\zeta(4) = \frac{36}{17} \sum_{n=1}^\infty \frac{1}{n^4\binom{2n}{n}}\)



메모

\[\sum_{n=1}^\infty \frac{1}{n^3\binom{2n}{n}}=-\frac{\zeta(3)}{3}-\frac{\pi\sqrt{3}}{72}(\psi^{(1)}(\frac{1}{3})-\psi^{(1)}(\frac{2}{3}))\] 바른 공식은 다음과 같다. \[\sum_{n=1}^\infty \frac{1}{n^3\binom{2n}{n}}=\frac{\pi\sqrt{3}}{18}(\psi^{(1)}(\frac{1}{3})-\psi^{(1)}(\frac{2}{3}))-\frac{4}{3}\zeta(3)\] 여기서 \(\psi^{(1)}\)는 트리감마(trigamma)함수. 트리감마 함수(trigamma function)항목 참조



관련된 항목들


매스매티카 파일 및 계산 리소스


사전 형태의 자료


관련논문

  • Bruner, Marie-Louise. ‘Central Binomial Coefficients Also Count (2431,4231,1432,4132)-Avoiders’. arXiv:1505.04929 Null, 19 May 2015. http://arxiv.org/abs/1505.04929.
  • Renzo Sprugnoli, Sum of reciprocals of the Central Binomial Coefficients, Integers: electronic journal of combinatorial number theory, 6 (2006) A27, 1-18
  • Bailey, David H., Jonathan M. Borwein, and David M. Bradley. 2005. “Experimental Determination of Apery-Like Identities for Zeta(2n+2).” Lawrence Berkeley National Laboratory (May 11). http://escholarship.org/uc/item/7wd7j9nz.
  • Borwein, Jonathan M., and Roland Girgensohn. 2005. “Evaluations of Binomial Series.” Aequationes Mathematicae 70 (1-2) (September 1): 25–36. doi:10.1007/s00010-005-2774-x.
  • Borwein, J. M., D. J. Broadhurst, and J. Kamnitzer. 2000. “Central Binomial Sums, Multiple Clausen Values and Zeta Values.” arXiv:hep-th/0004153 (April 22). http://arxiv.org/abs/hep-th/0004153.
  • [Lehmer1985] Lehmer, D. H. 1985. “Interesting Series Involving the Central Binomial Coefficient.” The American Mathematical Monthly 92 (7) (August): 449. doi:10.2307/2322496.
  • Zucker, I. J. 1985. “On the Series \(\sum_{k=1}^{\infty}\binom{2n}{n}^{-1}k^{−n}\) and Related Sums.” Journal of Number Theory 20 (1) (February): 92–102. doi:10.1016/0022-314X(85)90019-8.
  • A.J. Van der Poorten. Some wonderful formulas ... an introduction to polylogarithms, Queen's papers in Pure and Applied Mathematics, 54 (1979), 269-286

관련도서

메타데이터

위키데이터

Spacy 패턴 목록

  • [{'LOWER': 'central'}, {'LOWER': 'binomial'}, {'LEMMA': 'coefficient'}]