Fibonacci Day (1, 1, 2, 3) honors the medieval Italian mathematician Leonardo Bonacci, who was also known as Leonardo of Pisa and Leonardo Fibonacci. The talented number theorist introduced the world to mathematical concepts, such as the Arabic numbering system and Fibonacci number sequencing. The Fibonacci sequence—a sequence in which each number is the sum of the two preceding ones—is often represented as a spiral known as the golden ratio. The golden spiral corresponds to numerous features an