Fibonacci Day 1609

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 1609?

Fibonacci Day 1609 is on Monday, 23 November 1609.

What day of the week is Fibonacci Day 1609?

It falls on Monday.

How is Fibonacci Day calculated?

This event is observed every year on 23 November.