# A mathematical proof involving binomial coefficients and Pascal's Triangle

**URL:** <https://boards.straightdope.com/t/a-mathematical-proof-involving-binomial-coefficients-and-pascals-triangle/222597>\
**Category:** Factual Questions\
**Created:** [January 4, 2004, 6:13am UTC](https://boards.straightdope.com/t/a-mathematical-proof-involving-binomial-coefficients-and-pascals-triangle/222597 "2004-01-04T06:13:56Z")\
**Posts on this page:** 1\
**Page:** 2

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**Author:** ![Achernar](https://avatars.discourse-cdn.com/v4/letter/a/e274bd/32.png) [@Achernar](https://boards.straightdope.com/u/Achernar)\
**Post date:** [January 6, 2004, 8:13am UTC](https://boards.straightdope.com/t/a-mathematical-proof-involving-binomial-coefficients-and-pascals-triangle/222597/21 "2004-01-06T08:13:50Z")

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> [@](#):
>
> \*Originally posted by tFr \*  
> B is an element of the set {sum(from i=0 to n)[(n C i)]\*sum(from j=0 to k)[(k C j)]}

I think you have the right understanding, but your notation is confused. Are you treating a summation as a set consisting of its terms?

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