Catalan
# Eugène Charles Catalan

### Born: 30 May 1814 in Bruges, Belgium

Died: 14 Feb 1894 in Liège, Belgium

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**Catalan** was in Liouville's class at École Polytechnique in 1833 but was expelled from the École Polytechnique the following year. Allowed to resume his studies in 1835 he graduated and obtained a post at Châlons sur Marne.

With Liouville's help he obtained a lectureship in descriptive geometry at École Polytechnique in 1838 but his career was damaged by being very politically active with strong left-wing political views. Catalan published extensively on continued fractions and number theory.

He defined the numbers, called today the Catalan numbers, while considering the solution of the problem of dissecting a polygon into triangles by means of non-intersecting diagonals.

Catalan was not the first to solve the problem, however, since Segner had solved it in the 18 th century, although his solution was not as elegant as Catalan's. Euler had worked on simplifying the solution to the problem as did Binet at almost the same time as Catalan, around 1838.

**References (4 books/articles)**

**References elsewhere in this archive:**

For information about Catalan numbers see some pages by Robert M Dickau

**Other Web sites:**

Some information about
Catalan's constant

JOC/EFR February 1997