Fibonacci Day
This holiday is featured in the Obscure Holiday Calendar app with emoji-style visuals, reminders, and daily fun facts.
Overview
Fibonacci Day, observed annually on November 23rd (11/23), celebrates the famous Fibonacci sequence. This mathematical sequence, where each number is the sum of the two preceding ones, was introduced to the Western world by the Italian mathematician Leonardo Pisano, known as Fibonacci. It's a day to appreciate the beauty and pervasive nature of mathematics in art, science, and the natural world.
Observed each year on November 23, Fibonacci Day invites people to pause, share the story, and bring a little themed joy to their day.
Origin and story
The date 11/23 is chosen for Fibonacci Day because it visually represents the first four numbers of the sequence: 1, 1, 2, 3.
Leonardo Pisano (c. 1175 – c. 1250) was given the posthumous nickname 'Fibonacci,' which is believed to be a contraction of 'filius Bonacci,' meaning 'son of Bonacci.'
Quick facts
- DateNovember 23
- TypeNature / Outdoors
- Great forGardeners, Hikers, Eco clubs
Also on this date
Ways to celebrate
- Plant something small—herbs, seeds, or a window box.
- Fibonacci Day lands on November 23 — host a quick nod with Gardeners, Hikers and snap a photo.
- Write a note or journal entry on why Fibonacci Day matters, then set a reminder for next year.
- Share one fast fact about Fibonacci Day: The date 11/23 is chosen for Fibonacci Day because it visually represents the first four numbers of the sequence: 1, 1, 2, 3.
- Plan a 10-minute activity that fits the nature / outdoors vibe and make it a mini tradition.
Fun facts
- The date 11/23 is chosen for Fibonacci Day because it visually represents the first four numbers of the sequence: 1, 1, 2, 3.
- Leonardo Pisano (c. 1175 – c. 1250) was given the posthumous nickname 'Fibonacci,' which is believed to be a contraction of 'filius Bonacci,' meaning 'son of Bonacci.'
- The Fibonacci sequence famously appears in nature, from the arrangement of leaves on a stem and the branching of trees to the spirals of a sunflower seed head and the shell of a nautilus.
- The sequence is closely related to the Golden Ratio (approximately 1.618), a mathematical constant found throughout art, architecture, and design, often considered aesthetically pleasing.
- Fibonacci's most famous problem, often called the 'rabbit problem' from his book *Liber Abaci*, demonstrated the sequence's growth pattern based on a theoretical rabbit population.
Sources and attribution
Source not provided.
Continue to
FAQ
- When is Fibonacci Day?
- It is observed on November 23 each year.
- What is Fibonacci Day?
- Fibonacci Day, observed annually on November 23rd (11/23), celebrates the famous Fibonacci sequence. This mathematical sequence, where each number is the sum of the two preceding ones, was introduced to the Western world by the Italian mathematician Leonardo Pisano, known as Fibonacci. It's a day to appreciate the beauty and pervasive nature of mathematics in art, science, and the natural world.
- How do people celebrate Fibonacci Day?
- Plant something small—herbs, seeds, or a window box.
Get the app
Thousands of obscure holidays, daily widgets, reminders, and fun facts—free on iOS and Android.