Curiosities · Foundation · 5 min

Pascal’s triangle

Pascal’s triangle encodes combinations through a local addition rule.

WHAT HAPPENS IF…Why is C(5,2)=10?
Interactive exploration
Loading the mathematical model…

Connect the picture to the idea(nk)=(n−1k−1)+(n−1k)\binom nk=\binom{n-1}{k-1}+\binom{n-1}k

To choose k objects from n, separate selections into those containing one distinguished object and those excluding it. Their counts are C(n−1,k−1) and C(n−1,k). Edge entries equal 1. Summing a row counts all subsets, giving 2ⁿ.

A detail that matters

The parity picture is a finite pattern; it does not contain infinitely many rendered details.

Keep the connection going

One idea leads to another.

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