Reprinted from yesterday's late editions

Like the grand finale in a Hollywood production of the good old days, it would have made Jeanette MacDonald and Maurice Chevalier proud.

In the midst of the last refrain from "The Merry Widow," Metropolitan Opera star Beverly Sills stepped off the stage at the White House Tuesday, walked over to the president of the United States and, opening her arms, pulled him on to the dance floor for a waltz.

As prearranged, Metropolitan baritone Alan Titus gathered Rosalyn Carter into his arms simultaneously to waltz her around the floor while erenading her in duet with Sills.

It was the Carters' second social triumph in less than a week. On Sunday, they hosted the Horowitz piano recital, and Tuesday they entertained the nation's governors who were winding up their midwinter conference here. There was an understated sophistication that combined waltzes, light opera, candlelit tables, and champagne and crepes flambe, which may be the emergence of the long-awaited Carter social style.

"I've been here under Presidents Ford and Nixon, and I've never seen the White House look better," said Delaware's Gov. Pierre D. du Pont. "The fresh flowers, the table arrangements, everything. Mrs. Carter really gets an A-plus for this affair."

The evening began cabaret-style in the mansion's East Room where a Marine band played waltzes for anyone who knew how to dance them.

Vice President Walter Mondale was engrossed in conversation with South Dakota's Gov. Richard F. Kneip and Pennsylvania's Gov. Milton J. Shapp. A few tables away sat Joan Mondale with Connecticut's Gov. Ella Grasso and Georgia's Gov. George B. Busbee and their spouses. Across the room, Arizona Gov. Wesley Bolin was the first to ask Mrs. Carter to dance.

Amy Carter, wearing a long blue velvet dress, sat with her brother Chip, and his wife, Caron, until Sills and Titus started to sing, then she cut out for parts unknown.

Chip and Caron, who have taken up temporary residence in the White House after an absence of several months, said they were "looking for a house all over the city but we're in no hurry because we have a nice place to live until we find one."

He said he will be working for the Institutional Development Corp., a private nonprofit organization concerned with cities and schools. He declined, however, to disclose his salary.

Sills, magnificent in a white gown, said it wasn't her first dance with a president but she declined to rate how Presidents Ford and Nixon compared with Carter on the dance floor.

Carter welcomed his guests to what he called "your home as well as ours," going on to mention, if incorrectly, that it had been occupied by every president since George Washington. (John and Abigail Adams were the first White House residents).

Carter peppered the crowd with several key White House aides as well as two cabinet officers, Secretary of Agriculture Bob Bergland, and Secretary of Energy James Schlesinger.

The State Dining Room had been closed off and 13 round tables set up instead in the Red, Green and Blue rooms. The Carters presided over the Blue Room with the Governors' Conference Chairman William Milliken of Michigan and his wife at their table. The Mondales were host in the Red Room, and Chip and Caron Cater performed that function in the Green Room.

"I've been here for the last five years," said Montana Gov. Tom Judge, "and tonight's the best yet. I remember when I was here at the same dinner under Nixon. Of course the food was superb and they did serve drinks, which they didn't tonight, but after dinner Nixon got up there and gave a 45-minute speech. He gave us his entire foreign policy from China to Israel. It wasn't exactly what you call a delightful evening at the White House."

Meanwhile, Gov. Milliken, who happened to be Rosalynn Carter's partner, said their dinner conversation had centered around "little things. . . personal things like life in the White House." Do the Carters like life in the White House? "In the main, yes," said Milliken, although he refrained from going into particulars.

However, added Milliken, he came away from the three-day conference --and Tuesday's soiree -- clearly impressed with Jimmy Carter.

"I think this is the best governors' conference I have attended. And I felt very comfortable with Carter. He's learning very fast and I think he's going to do a good job. And that's saying something coming from a good Republican like myself."