Tony winner Nanette Fabray appears with Joseph Bologna and Renee Taylor in Bermuda Avenue Triangle, a Taylor-and-Bologna-made comedy which opened May 11 -- Mother's Day -- at Off-Broadway's Promenade Theatre. Producers have booked the show there through October 12, when Two Pianos, Four Hands rolls its keyboards into the space.

By its close, Triangle will have played 44 previews and 177 regular performances. Spokesperson Michael Lichtfield (of Maya Associates) said there were no set plans for a tour, though venues on Atlantic City/Tahoe circuit are being discussed.

The six-character antic went into a short tryout in Los Angeles that lasted almost a year and played frequently to standing room only. The third stage comedy penned by the husband-and-wife comedy-team (after Lovers and Other Strangers and It Had To Be You), this one concerns two widows who are dumped by their daughters into an exclusive retirement community in Las Vegas and who (without the other knowing it) fall for the same seductive stranger.

A different Tony winner completed the title triangle in Los Angeles: Beatrice Arthur. "Bea was tired and wanted to take a breather," said Taylor. "She went back to television, which she thought was easy next to eight times a week."

The third member of the original company doing the New York run is Manny Kleinmuntz, a former rabbi who happens to play one in the comedy. The daughters have been recast. Ronnie Faron has been signed to play Fabray's daughter. Taylor's daughter Priscilla C. Shanks. "It's a whole different world today," says Taylor. "When I was young, everybody wanted to be on Broadway--that was The Thing. Now they want to stay in L.A. and get a series." Danny Daniels, a film and stage choreographer (The Tap Dance Kid), is directing the comedy, which has sets by James Noone, costumes by Gail Cooper-Hecht, lighting by Tharon Musser, and sound by Jon Gottlieb.

For tickets ($50) and information on Bermuda Avenue Triangle call (212) 239-6200.

-- By Harry Haun and David Lefkowitz