One is changing.
Uh-oh...  Two has to change because One has changed.
Two is changing.
Uh-oh...  Four has to change because Two has changed.
Four is changing.
Uh-oh...  Six has to change because Four has changed.
Six is changing.
Uh-oh...  Five has to change because Two has changed.
Five is changing.
Uh-oh...  Six has to change because Two has changed.
Six is changing.
Uh-oh...  Three has to change because One has changed.
Three is changing.
Uh-oh...  Six has to change because Three has changed.
Six is changing.