n+2 column nodes (left part : n+2 and higher)
This is by nature HOLD situation.
There 9 nodes in this column. They are H, Q, R, S, T, U, V, W, Y. Let’s have a ride.
H node
H is a choice node. At H you choose J or K for X. Until then, J and K has not been studied. They both are in the « any...