The assignment doesn't specify whether the vectors should be row or column vectors, both could be concatenated horizontally to create either a [6x5] matrix or a [1x30] row vector. There are many ways to accomplish either interpretation and with some trial-and-error and some google'ing you'll succeed!
The code in your question is overwriting the vector on each iteration of the for-loop so you'll always end up with a 1x6 vector.
