"5] Go to the hardware store and buy a small rubber thing made to seal
the laundry hose to the pipe. They are sold just for that purpose.
They are gray rubber-like material. They slip over the 1 1/2" PVC,
and the approx. 1 inch hose fits into it. There is a hose clamp on
both sides of it. Problem solved !!! "

Unless the sewer gas then makes it's way out of the washer itself.
Plus, if the house gets an inspection when you decide to sell it, this
is something obvious that will get flagged without having a trap.