SAS airlines has Los Angeles to Copenhagen on sale at $543 round trip for departures from November to March 2017. This sale has far more limited departure dates than the deals out of San Francisco to numerous cities in Norway and Sweden for even less over the same time period, but Copenhagen is not on sale from SFO. Less than half the dates are available at low fares for LAX to Copenhagen and airports in Norway and Sweden are priced in the $600s and $700s from LAX.
Loyalty Traveler – SAS San Francisco to Norway or Sweden $528-$544 round trip Nov-March
SAS Los Angeles – Stockholm ARN – Copenhagen CPH – ARN – LAX