This example demonstrates a recursive factorial calculation using plain JavaScript, displaying the result of factorialize(4)—the value 24—in large, centered text on the page. The code defines a recursive function that multiplies a number by the factorial of its decremented value until reaching zero, logging the answer to the console and rendering it directly in the DOM. It uses D3 v7 only to load the library via a script tag, while the visualization itself relies on standard HTML, CSS, and JavaScript recursion rather than any D3-specific API or data binding.