\prod _{i=1}^{6}i
Or even by ASCII symbols https://latex.codecogs.com/png.image?\dpi{110}%20\prod%20_{i=1}^{6}i
Instead of code like
var value = 1 for (var i = 1; i <= 6; i++) { value *= i }
The book Structure and Interpretation of Classical Mechanics uses both a modified traditional notation as well as runnable Scheme throughout. I recommend reading at least the preface:
https://mitpress.mit.edu/sites/default/files/titles/content/...
I don't know APL, but it seems the most condensed language for doing mathematical stuff. In APL (I looked it up) you'd write "!6". Try/learn APL online here https://tryapl.org/
In Julia you can use Unicode characters as variable names, write e.g. "2π" instead of "2*PI", and it's easy to "operator overload", so that e.g. "+" adds/combines together 2 or more of whatever things you want to add/combine, whatever they are, in whatever way you like. Or add new operators. Thus lines of code in Julia can get a lot closer to looking like mathsy/sciency expressions than in most languages.