The Gauss Summation.

S = 1+2+..+n , Also S = n+(n-1)+..+2+1 , Adding two will get n+1 , n times , this 2S = (n+1)n , or S = n(n+1)/2.

1+2+....+10= (1+10)+(2+9)+(3+8)+(4+7)+(5+6)= 11*5= (10+1) *10/2 10=n, 10+1=n+1, 10/2=n/2 =(n+1)n/2

These videos showing a visual for what's happening mathematically are brilliant. So helpful.

Great 😮

Geometry makes mathematics much more intuitive

👌👌

You know there is also the Pyramid one analysis

Which software you used to create the visual?

That is so brilliant