UA 1638 then DL 972 at LAX
Denver → Los Angeles → New York JFK
Timetable, Los Angeles time
09:34UA 1638 from Denver at the gate
08:25DL 972 to New York JFK leaves the gate
22 h 51 apart on the timetable, overnight
DL 972 leaves 22 h 51 after UA 1638 arrives on the timetable: more than half a day, so not a connection we count.