shapeArea - I need tips :c

Hello everyone, I would like your help with a question called shapeArea.

I have had some difficulty applying logic to this exercise.

A 1 -interesting polygon is just a square with a side of length 1 . An n -interesting polygon is obtained by taking the n - 1 -interesting polygon and appending 1 -interesting polygons to its rim, side by side.

image

What is the best tip you can give me regarding the content of this question?

… and what is the actual question?