How can someone type this capcha?

Assume A is vector/matrix related:

You cant have A ^ n (unless A is an m x m matrix), but this is ||A|| ^ n which is perfectly fine. ||A|| is the magnitude of A (which we assume is a vector), and the magnitude of A is just a number... nothing wrong with raising a number to the power of n.

This is ||A^n||, not ||A||^n. It's only the same thing when you consider A to be a number, no?