Complex sentence: William Brouncker, 2nd Viscount Brouncker, PRS (1620--5 April 1684) was an English mathematician who introduced Brouncker's formula, and was the first President of the Royal Society.
Split into simpler sentences: William Brouncker, 2nd Viscount Brouncker, PRS (1620--5 April 1684) was an English mathematician who introduced Brouncker's formula. He was one of the founders and the first President of the Royal Society.