The world could use some good luck these days. Unfortunately, Ireland’s fabled solution — finding a four-leaf clover — remains as hard as ever to pull off this Saint Patrick’s Day. That’s because the difference between three and four leaves is more than just aesthetic: The single leaf that divides them represents the lucky shamrock’s fuck-you to Fibonacci’s celebrated numerical law, which usually doesn’t run into issues forcing nature’s patterns to follow its lead.

A quick refresher on the Fibonacci sequence: Fibonacci was an Italian guy living in the Middle Ages who realized that, when rabbits make babies, they produce them in numbers that conform to a pattern. That pattern — in which each successive number is the sum of the two previous numbers — turned out to not just dictate the growth of bunny populations but an astounding wealth of other patterns in nature, like the spiral of sunflower seeds or the twirl of a head of fractal broccoli. The three leaves of a regular clover are thought to fit into this framework, too.

In 1994, a Swarthmore College mathematician answered a query about the rarity of four-leaf clovers by stating simply, “Four is not a Fibonacci number.” It’s true — the sequence begins 0, 1, 1, 2, 3, 5, 8, 13, 21, and continues indefinitely. The idea behind this statement is that nature seems to favor growth that follows the Fibonacci sequence, and so when a clover sprouts an extra leaf, it does so in defiance of this natural, mathematical law. The world’s wealth of three-leaved clovers tells us that most shamrocks are conformists while the four-leaved ones are renegades.