Washington, D.C., this fall offers visitors and residents alike an array of special events - museum openings, world-class artistic performances, special concerts, sports events, and more. A few of the attractions are these:
Sept. 26-27 and Sept. 29-Oct. 1 - ''Dance America,'' at the Washington Performing Arts Society.
Sept. 28-Jan. 8 - At the National Gallery of Art, ''Art of Aztec Mexico: Treasures of Tenochtitlan,'' An exhibition of objects from the Great Temple of Tenochtitlan, capital of the Aztec Empire in Mexico.
Sept. 30-Oct. 11 - In historic Georgetown, an authentic Oktoberfest with lively German bands and cultural food to help celebrate the 300th anniversay of German immigration to the United States.
Oct. 7-16 - The New Music America Festival, 16 concerts ranging from Eskimo throat singers to electronic synthesizers. For information on where the different concerts will be held call (202) 347-4717.
Oct. 19-Jan. 22 - At the National Museum of American Art, ''The Capital Image: Painters in Washington, 1800-1915,'' 200 paintings, 25 prints, 50 photographs and sculpture by early artists in the nation's capital.
Nov. 29-Dec.4 - Paul Taylor Dance Company, at the Washington Performing Arts Society.
Visitors are prompted to pick up the free quarterly Sights and Sounds brochure published by the Washington Convention and Visitors Association for further information on events around the city.