The outstanding Indian mathematician of modern times. Originally a clerk in Madras, he studied and worked on mathematics totally unaided. Following correspondence with G. H. Hardy, he accepted an invitation to visit Britain in 1914. He studied and collaborated with Hardy on the subject of partitions and other topics in number theory. He was considered a genius for his inexplicable ability in, for example, the handling of series and continued fractions. Because of ill health he returned to India a year before he died.