Forgotten Tree 9

There is a rooted binary tree with $N$ nodes. For each node with exactly two children, one of them is called the left child and the other is called the right child. If a node has only one child, it is still specifically called either the left child or the right child. The nodes are labelled $1$ through $N$ according to the inorder traversal of the tree. That is, the labelling can be generated b