 From 1837 , Alkan lived in the Square d <unk> in Paris , which was inhabited by numerous celebrities of the time including Marie <unk> , Alexandre Dumas , George Sand , and Chopin . Chopin and Alkan were personal friends and often discussed musical topics , including a work on musical theory that Chopin proposed to write . By 1838 , at 25 years old , Alkan had reached a peak of his career . He frequently gave recitals , his more mature works had begun to be published , and he often appeared in concerts with Liszt and Chopin . On 23 April 1837 Alkan took part in Liszt 's farewell concert in Paris , together with the 14 @-@ year @-@ old César Franck and the virtuoso Johann Peter <unk> . On 3 March 1838 , at a concert at the piano @-@ maker <unk> , Alkan played with Chopin , Zimmerman , and Chopin 's pupil Adolphe <unk> in a performance of Alkan 's transcription , now lost , of two movements of Beethoven 's Seventh Symphony for two pianos , eight hands . 
