You can do it on a single airline if you nest round trips within one-ways e.g.

Flight 1:
PDX-SFO Monday Week 1 (one-way)

Flight 2:
SFO-PDX Wed Week 1, return PDX-SOF Mon Week 2

Flight x:
SFO-PDX Wed Week n, return PDX-SFO Mon Week n+1

Flight y:
SFO-PDX final flight home, end of engagement.

I did this for some long term contracts in the past to get the saturday night stays in. It's not nesting because you've got a 1-way, then treat your "remote" airport as your "home" airport.... flying home for the weekend over Sat Night, returning to work the following week.