how to create random combination?

How to create random combination of three integer of length 21. for example ans=1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 and next time answer should be in random order.

[the cyclist]

You haven't been clear or complete enough in your description. I can't guess what you want. Please add more details.

Answer 1

[Azzi Abdelmalek]

repmat(randperm(3),1,7)