Rowland Leonard Brooks was an English mathematician, known for proving Brooks' theorem on the relation between the chromatic number and the degree

Degree (graph theory)

In graph theory, the degree of a vertex of a graph is the number of edges incident to the vertex, with loops counted twice. The degree of a vertex v is denoted \deg. The maximum degree of a graph G, denoted by Δ, and the minimum degree of a graph, denoted by δ, are the maximum and minimum degree...

 of graphs. He studied at Trinity College

Trinity College, Cambridge

Trinity College is a constituent college of the University of Cambridge. Trinity has more members than any other college in Cambridge or Oxford, with around 700 undergraduates, 430 graduates, and over 170 Fellows...

, Cambridge University, and also worked with fellow Trinity students W. T. Tutte

W. T. Tutte

William Thomas Tutte, OC, FRS, known as Bill Tutte, was a British, later Canadian, codebreaker and mathematician. During World War II he made a brilliant and fundamental advance in Cryptanalysis of the Lorenz cipher, a major German code system, which had a significant impact on the Allied...

, Cedric Smith, and Arthur Harold Stone

Arthur Harold Stone

Arthur Harold Stone was a British mathematician born in London, who worked mostly in topology. His wife was American mathematician Dorothy Maharam...

 on partitions of rectangle

Rectangle

In Euclidean plane geometry, a rectangle is any quadrilateral with four right angles. The term "oblong" is occasionally used to refer to a non-square rectangle...

s into square

Square (geometry)

In geometry, a square is a regular quadrilateral. This means that it has four equal sides and four equal angles...

s, both under their own names and under the pseudonym

Pseudonym

A pseudonym is a name that a person assumes for a particular purpose and that differs from his or her original orthonym...

 Blanche Descartes

Blanche Descartes

Blanche Descartes was a collaborative pseudonym used by the English mathematicians R. Leonard Brooks, Arthur Harold Stone, Cedric Smith, and W. T. Tutte. The four mathematicians met in 1935 as undergraduate students at Trinity College, Cambridge, where they joined the Trinity Mathematical Society...

.

After leaving Cambridge, he worked as a tax inspector.