Dear Mr. Fibonacci

Dear Leonardo of Pisa, of the Bonacci family,

Happy Fibonacci Day! Thank you for your hard work, your extensive travels, and your diligence and devotion to bring numbers and mathematics from the east to the west.

Thank you for handing down to us so many joyful mathematical puzzles, experiences and inspiration! Are you aware that some people now, in 2024, say you changed the world?

How did you manage as a teenager to travel by land and sea in the 13th century?

“When I had been introduced to the art of the Indians’ nine symbols through remarkable teaching, knowledge of the art very soon pleased me above all else and I came to understand it, for whatever was studied by the art in Egypt, Syria, Greece, Sicily and Provence, in all its various forms.”
—Fibonacci, in his famous book Liber Abaci.

Are you wondering why are we celebrating “FIBONACCI DAY” today? Because it’s the 11th month and the 23rd day. Get it? 1, 1, 2, 3, ….. the sequence?

Yes, yes, I know it wasn’t a major focus of your work, but … remember that rabbit problem? Well, now we all call that “The Fibonacci Sequence”. No word of a lie. And we love seeing the patterns in nature that show the Fibonacci Numbers.

You know, if not for you, we’d probably be trying to add, multiply and divide Roman numerals. Like….
CMXLIV + DXXXIX = __ (How would we add that? Would we just add like terms ????)

We applaud you for writing lengthy books, by hand. Now imagine this: one of your books, Leonardo of Pisa’s Liber Abaci (Book of Calculation), is still available one thousand years later! Can you believe it? It has been translated, 800 years later, from Latin into English.

Now, there are about 2,000 books written about you, and your mathematical discoveries and puzzles! Adults and children love them.

There is even a Fibonacci Quarterly academic publication, that has been published for the past 60 years, edited by scholars around the world. There have been five International Conferences on Fibonacci Numbers and Their Applications. Did you ever dream you would have such fame?

Get this: the most prestigious piano makers, Steinway & Sons, marked the occasion of crafting their 600,000th piano by creating “The Fibonacci” , saying, “combining the universal languages of music and mathematics made perfect sense.”

I think you get the point.

Thanks for celebrating Fibonacci Day with us, Leonardo of Pisa!

Answer to Roman numerals problem:
We can’t just add like terms because : the C (100) before the M (1000) means 900, the X (10) before the L (50) means 40,
the I (1) before the V (5) means 4, the I (1) before the X (10) means 9. So…. CMXLIV + DXXXIX = MCCCCVXXXIII. But it’s so much easier to use Arabic numbers: 944 + 539 = 1483!

My appreciation to the following for images: mocomi.com (GIF); Steinway & Sons; 99designs-blog.imgix.net; https://www.historymath.com/fibonacci/ for “What you can Blame Fibonacci for Having to Learn” ; https://faculty.evansville.edu/ck6/bstud/fibo.html for the photo of the statue of Fibonacci in Pisa