CREATE TABLE table_2668336_19 (incumbent VARCHAR, result VARCHAR, first_elected VARCHAR)

Who were the incumbent(s) when the result was a retired democratic-republican hold and the first elected representative was in 1816>
SELECT incumbent FROM table_2668336_19 WHERE result = "Retired Democratic-Republican hold" AND first_elected = "1816"
SELECT "incumbent" FROM "table_2668336_19" WHERE "1816" = "first_elected" AND "Retired Democratic-Republican hold" = "result"