Stella's Place

WeeWeed just reminded me that this is one of Menagerie’s favorite days, so . . .

The Fibonacci sequence. Named for Leonardo of Pisa, popularly known as Leonardo Fibonacci.

As Wikipedia explains it, in mathematics, the Fibonacci numbers, commonly denoted Fₙ form a sequence, called the Fibonacci sequence, such that each number is the sum of the two preceding ones, starting from 0 and 1. That is, F₀=0, F₁=1, and Fₙ=Fₙ₋₁+Fₙ₋₂, for n > 1. One has F₂ = 1. In some books, and particularly in old ones, F₀, the “0” is omitted, and the Fibonacci sequence starts with F₁ = F₂ = 1. The beginning of the sequence is thus: (0,) 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, … Fibonacci numbers are strongly related to the golden ratio: Binet’s formula expresses the nth Fibonacci number in terms of n and the golden ratio, and implies that the ratio of two consecutive Fibonacci numbers tends to the golden ratio as n increases.

November 23 is celebrated as Fibonacci day because when the date is written in the mm/dd format (11/23), the digits in the date form a Fibonacci sequence: 1,1,2,3.

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