Trivia on Pancham, taken from wikipedia:
According to stories, Rahul Dev Burman was nicknamed PANCHAM because, as a child, whenever he cried, it sounded in the fifth note (Pa) of the Indian musical scale. The word Pancham means five (or fifth) in Bengali and Sanskrit. Another version is that when the veteran Indian actor Ashok Kumar saw a newborn Rahul Dev Burman uttering the syllable Pa repeatedly, he nicknamed the boy Pancham.