Problem Link - [https://www.iarcs.org.in/inoi/online-study-material/topics/dp-tiling.php](https://A more complicated tiling problem)

In this edutorial there is two problem.

part-1) Some tiling problems (I understand this completely)

part-2) A more complicated tiling problem (I have doubt in this)

the recurrence relation is **f(n) = f(n-1) + f(n-2) + 2g(n-2)**

I have doubt in function **g(n) → (covering n*2 grid using L-shaped tile)**

here after using one L-shaped tile and then calling for g(n-2), i think there will be one uncovered square.

is the recurrence relation is correct.

please elaborate.