Its just for Loops

btw these large scary math symbols are just for-loops

@FreyaHolmer

Freya Holmér’s 2021 tweet expanded my understanding of maths in a small but genuinely important way. Σ\Sigma and Π\Pi — those symbols that look like they belong to a completely different discipline — are just for loops with a fancier hat.

Summation (capital sigma)
∑n=043n\displaystyle\sum_{\textcolor{#56d6b3}{n=0}}^{\textcolor{#e05c75}{4}} \textcolor{#6bb8f5}{3n}
sum = 0;
for( n=0; n<=4; n++ )
    sum += 3*n;
Product (capital pi)
∏n=142n\displaystyle\prod_{\textcolor{#56d6b3}{n=1}}^{\textcolor{#e05c75}{4}} \textcolor{#6bb8f5}{2n}
prod = 1;
for( n=1; n<=4; n++ )
    prod *= 2*n;

I never would have made that connection on my own. Predictably, the replies descended into pedantry — mathematicians insisting the analogy was imprecise, missing the point entirely. Freya was trying to make something feel less intimidating, and it worked.