Former President George W. Bush and former President Barack Obama were also present at the funeral, and five current and former presidents filled the front row of the cathedral.
When Trump arrived at the funeral home, he shook hands awkwardly with former Vice President Pence.
This is the first time President-elect Trump has met with the so-called "President's Club," an informal gathering of former and current presidents who survived after winning the November 5 presidential election.
Trump sat next to former President Obama and the two were seen smiling and talking before the event.
Former President Obama also greeted Vice President Kamala Harris on the same day.
Trump, who sat next to him, did not speak to Vice President Harris.
Former and current presidents met behind closed doors before the funeral, an unusual display of harmony seen in deeply divided U.S. politics, the Associated Press and others said.
AI Anchor: Y-GO
Caption editing: Jeong Eui-jin
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