<Li> Kennedy Center Honors </Li> <P> Ray Charles (born Charles Raymond Offenberg; September 13, 1918--April 6, 2015) was an American musician, singer, songwriter, vocal arranger and conductor who was best known as organizer and leader of the Ray Charles Singers who were featured on Perry Como's records and television shows for 35 years and were also known for a series of 30 choral record albums produced in the 1950s and 1960s for the Essex, MGM, Decca and Command labels . </P> <P> As a vocalist, Charles, along with Julia Rinker Miller, sang the theme song to the television series Three's Company ("Come and Knock on Our Door"). As a songwriter, Charles was best known for the choral anthem "Fifty Nifty United States" in which he set the names of the states to music in alphabetical order . It was originally written for The Perry Como Show . He is also known for "Letters, We Get Letters", also originally written for Como's show and later used on the Late Show with David Letterman . </P> <P> In his later years, he continued to serve as a musical consultant to television programs, most notably for 31 years on the Kennedy Center Honors . Charles was acknowledged as an authority on American popular music . </P>

Who sings the three's company theme song
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