Leonardo of Pisa (c1170-1241+), better known as Fibonacci, wrote Liber Abaci to introduce and advocate the adoption of “Indian figures” (Hindu-Arabic numerals) to Italy. The book explains how to perform arithmetic and common business problems using the digits and a positional number system. Leonardo uses a composed fractions (aka composite fractions, aka linked fractions) notation to express mixed radix quantities (i.e. positional numbers where the base varies by position). This notation lasted about 300 years until the adoption of decimal fractions. Drawing from his examples, we derive algorithms for the arithmetic operations in recipe and in formal Typescript representations.
George Boole (1815-1864) was a mathematician best known as the progenitor of the Boolean algebra, the system of logic that acts as a fundamental layer within digital systems. Although he never gained a college degree, he spent many productive years as the chair of mathematics at Queen’s College, Cork. Desmond MacHale’s The Life and Work of George Boole is a well-written exploration of Boole’s life, personality, and impact.
In 1971, three college roommates developed an educational computer game. Titled OREGON, it was a simulation of westward migration along the Oregon Trail and proved to be a hit among the students. One of the designers, Don Rawitsch, later carried a copy of the source code to his new employer, Minnesota Educational Computing Consortium (MECC). From 1975 to 1983, OREGON was MECC’s most popular courseware on their timeshare service. When MECC decided a new version was merited, which became The Oregon Trail, they mandated the design team to “preserve whatever made the original so popular.” With the availability of the source code for the 1975 and 1978 versions, we explore the design and implementation of OREGON and why it was popular and memorable.
In Fifth Edition (5e) Dungeons & Dragons™ (D&D), druids can transform into certain Beast forms using the Wild Shape ability. Similarly, casters of the Polymorph spell can transform allies and enemies into Beasts. Players often find selecting a Beast form onerous (there are 84 forms defined in the System Reference Document (SRD) alone) as this is a multi-dimensional decision problem.