Difference between revisions of "Binomial coefficient"
From specialfunctionswiki
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=References= | =References= | ||
− | * {{BookReference|Handbook of mathematical functions with formulas | + | * {{BookReference|Handbook of mathematical functions with formulas|1964|Milton Abramowitz|author2=Irene A. Stegun|prev=Binomial theorem|next=Binomial coefficient (n choose k) equals (n choose (n-k))}}: 3.1.2 |
*[http://dualaud.net/specialfunctionswiki/abramowitz_and_stegun-1.03/page_10.htm Abramowitz and Stegun]<br /> | *[http://dualaud.net/specialfunctionswiki/abramowitz_and_stegun-1.03/page_10.htm Abramowitz and Stegun]<br /> | ||
*[http://www.jstor.org/discover/10.2307/2975209?sid=21105065140641&uid=4&uid=70&uid=2&uid=3739256&uid=3739744&uid=2129 The Binomial Coefficient Function]<br /> | *[http://www.jstor.org/discover/10.2307/2975209?sid=21105065140641&uid=4&uid=70&uid=2&uid=3739256&uid=3739744&uid=2129 The Binomial Coefficient Function]<br /> | ||
[[Category:SpecialFunction]] | [[Category:SpecialFunction]] |
Revision as of 02:33, 4 June 2016
The binomial coefficients are defined by the formula $${}_nC_k:={n \choose k} = \dfrac{n!}{(n-k)!k!}.$$
Properties
Proposition: $\displaystyle{n \choose k} = {n \choose {n-k}} = (-1)^k {{k-n-1} \choose k}$
Proof: █
Proposition: $\displaystyle{{n+1} \choose k} = {n \choose k} + {n \choose {k-1}}$
Proof: █
Proposition: ${n \choose 0} = {n \choose n} = 1$
Proof: █
Proposition: $1 + \displaystyle {n \choose 1} + {n \choose 2} + \ldots + {n \choose n} = 2^n$
Proof: █
Proposition: $1 - \displaystyle {n \choose 1} + {n \choose 2} - \ldots + (-1)^n {n \choose n} =0$
Proof: █
Videos
Pascal's Triangle and the Binomial Coefficients
Example of choose function (Binomial Coefficient)
Binomial coefficients