This example demonstrates a minimal JavaScript array manipulation workflow, showing how to generate a sequence of numbers and transform it into an array of objects with computed properties. The code defines a `range` function that pushes numbers from 0 to `n-1` into an array, then logs the initial sequence and a mapped version where each number is paired with its double. Built with plain HTML and JavaScript, it relies on native array methods like `push` and `map`, with no external libraries or frameworks. The console output serves as the primary visualization, illustrating the transformation steps directly.