Edouard LucasFrançois Edouard Anatole Lucas
(1842-1891) was a French mathematician who was educated at the École Normale Supérieure. He worked in the Paris observatory and later became a professor of mathematics in Paris. In the meantime he served in the army.
He known for his study of the Fibonacci sequence. The related Lucas sequence is named after him. He gave a formula for finding the nth term of the Fibonacci sequence.
He devised methods for testing the primality of numbers. Later Derrick Henry Lehmer refined his work and obtained the Lucas-Lehmer test for Mersenne numbers.
Lucas was also interested in recreational mathematics; the Tower of Hanoi puzzle was invented by him.