His main interests were the theory of numbers and recreational mathematics.

He is best known as the author of many books in recreational mathematics aimed at middle and high school students.

He wrote a number of books on recreational mathematics.

Figurate numbers have played a significant role in modern recreational mathematics.

Similarly, it maybe difficult to separate education from recreation as in the case of recreational mathematics.

He is known for discovering results in recreational mathematics.

He was a major proponent and supporter of recreational mathematics for decades.

Some mathematical games are of deep interest in the field of recreational mathematics.

Mathematical puzzles make up an integral part of recreational mathematics.

Palindromic numbers receive most attention in the realm of recreational mathematics.

Martin Gardner, the well-known recreational mathematics writer, said a few years ago that he believed and hoped so.

Some of these are recreational mathematics, others contributions to discrete mathematics.

The idea that Martin Gardner "created the field of recreational mathematics" is absurd.

He is known for his work in computational geometry, graph algorithms, and recreational mathematics.

The term is analogous to the term "recreational mathematics."

In recreational mathematics, a polydrafter is a polyform with a triangle as the base form.

He was an early computer buff, an enthusiasm that has stayed with him, and he still does "recreational mathematics."

Recreational mathematics - the area dedicated to mathematical puzzles and mathematical games.

The necklace problem is a problem in recreational mathematics, solved in the early 21st century.

Lucas was also interested in recreational mathematics.

Among his contributions to recreational mathematics are Rep-tiles.

The popularity of recreational mathematics is another sign of the pleasure many find in solving mathematical questions.

They are studied in recreational mathematics where palindromic numbers with special properties are sought.

Smullyan is the author of many books on recreational mathematics, recreational logic, etc.

MacMahon also did pioneering work in recreational mathematics and patented several successful puzzles.