There is no question that cultural programming on television is on the upswing. But instead of the vitality of the recent efforts of series like "Live from Lincoln Center," last night's PBS showing for Chinese Vice Premier Teng Hsiao-ping called "Barely Live from Kennedy Center."

It's the way these ceremonial events tend to turn out -- where the president declares the object to be to "demonstrate the diversity of our culture," and we get a mishmash that might discreetly be categorized as a potpourri.

The real question is that in the hour or so of the evening's entertainment, how do you fit John Denver, Rudolf Serkin, Shirley MacLaine, the Harlem Globertotters and Teng into the same program without many moments of incongruity -- at least that's the way it seemed on the television screen.

The reason why, of course, is politics. The esthetic high point of the eveing may have been Serkin's Schubert, but it could not be ignored that Teng has more of a passion for basketball than for Schubert. He positively glowed when the Trotters came out and started shooting baskets.

It shoud be asserted, though, that for all its clutter the eveing had several splendid moments. Certain moments rose above the cultural conglomeration. The swagger of two ragtime numberss from the roadway musical "Eubie" were indestructible, and delightful.

Even then, though, there were rough edges. The Characterization of Serkin by introducer I. M. Pei as "the finest musician of our times" must have been a little emberrassing to the pianist. He would hav felt more comfortable, one believes, with settling for the level of Pei himself as one of our time's finest architects.

Both Pei and MacLaine were on the show as hosts because they had been recent visitors to the People's Republic.A weak peg, indeed, for a show that was alredy showing its vulnerable points.

Exactlyu why John Denver singing "Rockly Mountain High" fitted into this spectale seemed unclear.But Denver did what he does at the best of his standards, and the audience was delighted.

The Joffery Ballet's finale -- the Copland-De Mille "Rodeo" -- seemed uncharacteristically tepid. It was supposed to be the most archetypically American number on the progam, and done this way American comes out sounding pretty bland.

Thanks to satellite, the observance many have one of the largest audiences in television's history. It was taped off an RCA satellite for broadcast in China, where the hours of the event were hardly prime time. It will be transmitted to that one fourth of the world's population at the appropriate time today.