John Tromp
John Tromp is a Dutch computer scientist. He formerly worked for Dutch Centre for Mathematics and Computer Science. Tromp discovered the number of legal states of the board game Go, and co-authored with Bill Taylor the Tromp-Taylor Rules, which they call "the logical rules of Go".
He is also known for Binary combinatory logic (Binary lambda calculus) and lambda diagrams that supply a graphical way of representing lambda calculus expressions.