Eugène Charles Catalan (French pronunciation: [øʒɛn ʃaʁl katalɑ̃]; 30 May 1814 – 14 February 1894) was a French and Belgian mathematician who worked on continued fractions, descriptive geometry, number theory and combinatorics. His notable contributions included discovering a periodic minimal surface in the space R 3 {\displaystyle \mathbb {R} ^{3}} ; stating the famous Catalan's conjecture, which was eventually proved in 2002; and introducing the Catalan numbers to solve a combinatorial problem. Source: Wikipedia (en)