#58 Lego lockdown
It is lockdown in my house and to keep the kids occupied, I have challenged them to find all the possible sequences when placing red 1×1 and blue 2×1 Lego blocks in a row.
There is only one way of making a row of length one (one red); there are two ways of getting a row of length two (B or RR); and three ways of getting a row of length three (BR, RB and RRR).
But after length three, the pattern seems to break down. There are five ways to get length four (BB, BRR,…
