How I do 'random'

I am making a granny hexagon blanket for my living room. The plan is to have three different shades of beige, cream and brown in the middle of each hexagon, then one round of red - and I have four different reds - and finally cream round that I will use to join all the hexagons as I go.
I wanted the middles to look scrappy and random. Some people would maybe just buy some yarn and would randomly pick a colour for every round. But my way of being random is to use formula to calculate how many different combinations  of three I can have with six colours and then with every group of three there is six possible combinations. This stage is now completed :)
In total I have 120 circles every one of them is three rounds of different colours and none two are the same :)

Now, the second stage: I have put all my groups of six in order I am going to join them and I have assigned two different reds to every group. Just to make sure that every red will be used evenly and spread evenly on the blanket.
Part of me would like to let go and just pull random yarns from he basket but a much bigger part enjoys my geeky approach to randomness...