SK 1842 then BA 781 at Arlanda
Rome → Stockholm → London Heathrow
Timetable, Stockholm time
23:55SK 1842 from Rome at the gate
18:10BA 781 to London Heathrow leaves the gate
18 h 15 apart on the timetable, overnight
BA 781 leaves 18 h 15 after SK 1842 arrives on the timetable: more than half a day, so not a connection we count.