How to define an array with multiple columns for each parameter in a for loop?

I have a loop where each parameter should create an array with 20 columns so for n=1, there's 20 columns in the array, n=2, there's 20 columns in the array etc; so the final array should have 20*sz columns but am not sure how to code this (attempt below):

for n=1:sz
  array(:,20]);
end

Answer 1

[James Tursa]

At each iteration, the array sub-section indexing would be:

array(:,n*20-19:n*20)