Fibonacci Day 1420

Thursday, 23 November 1420

Fibonacci Day uses the month and day notation 11/23 to echo the opening numbers of the Fibonacci sequence: 1, 1, 2, 3.

Frequently asked questions

When is Fibonacci Day 1420?
Fibonacci Day 1420 is on Thursday, 23 November 1420.
What day of the week is Fibonacci Day 1420?
It falls on Thursday.
How is Fibonacci Day calculated?
This event is observed every year on 23 November.