Fibonacci poetry (also called “fibetry”, or “fibs”) is a form of constrained writing using the Fibonacci sequence as the constraint.
The Fibonacci sequence is 1, 1, 2, 3, 5, 13, 21, 34, … Each new term is the sum of the previous two terms.
In Fibonacci poetry these number specify either the number of words or the number of syllables in each line (you can choose one or the other).
For example (using syllables):
The first line contains only 1 syllable.
And the second line contains only 1 syllable.
The third line contains just 2 syllables.
The fourth line contains only 3 syllables.
The fifth line contains only 5 syllables.
The sixth line contains only 8 syllables.
And so forth until you decide to stop, and the poem does not have to be about math.
Math Plus Poetry Yeilds The Fib.
by Gregory K Pincus
See the references for more examples of Fibonacci poetry.