Basically the author took the idea of chess boxing and then let his imagination run wild. For example: In one contest the fighters competed to factor a series of increasingly large numbers, with the winner getting the sum of the factors in seconds for a free attack on their opponent.
There is a free trial (in Japanese) at http://maoh.dengeki.com/try/bunburyoutou/index.html but that is geoblocked an image search using the kanji above should give you the idea.
Basically the author took the idea of chess boxing and then let his imagination run wild. For example: In one contest the fighters competed to factor a series of increasingly large numbers, with the winner getting the sum of the factors in seconds for a free attack on their opponent.