A certain stock exchange designates each stock with a 1, 2 or…

A certain stock exchange designates each stock with a 1, 2 or 3 letter code, where each letter is selected from the 8 letters of the alphabet. If the letters may be repeated and if the same letters used in a different order, constitute a different code, how many diff stocks is it possible to designate with these codes?

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #7172