Must be a multiple of 2
Must be a multiple of 1
Since workers can return an assignment or drop out, some "spare" participants will be created: the oTree session will have 2 times more participant objects than the number you enter here.
You can make more properties configurable by adding them to your session config in settings.py.
During this short experiment you will see various games as in the image below. We will first explain the meaning of this table.