It is called the Fibonacci sequence, after Leonardo Fibonacci of Pisa, circa 1202.
It is a numerical series in which the first two numbers are 0-1, and each subsequent number is the sum of the previous two.
It presents as follows: 0-1-1-2-3-5-8-13-21-34-55-89…. (The zero is often omitted.) On first inspection, it appears to be an interesting but unimportant play of numbers. An amusement. However, consecutive numbers in the sequence produce a ratio (“Golden Ratio”) that has significance in many areas: leaf and flower arrangement, sea shell structure, the pyramids of Egypt and Parthenon of Greece, Leonardo da Vinci’s Mona Lisa, the length of human body parts…. Google Search for Golden Ratio Articles
In the Fibonacci Watch, I have used the first five numbers in the sequence (1-1-2-3-5) as a time-telling method. The dial of the watch is rectangular–46mm x 36 mm–and divided into four sections. (Two examples, in different color combinations, one showing “time” and one “date,” are offered at the bottom of the page.) Each section contains a series of bars which, by being lit (red for time, green for date) or unlit, provides a code for numbers 0-9. (The code for each number is given below. It is the key to telling the time! The number for each section is the sum of the lit bars.)
(Study the dials below.) The top two sections of the dial represent hours (or month of the year in the date mode); the bottom two sections represent minutes (or day of the month in the date mode). Sections on the left represent the tens column; Sections on the right represent the units column. Pusher A is a time/date display; pusher B is a time/date set. The display would be constantly on, since “calculating” the time can take time! There is no AM/PM function.