PAD Challenge Day 11: The First G(r)eek Fan Letter?

 Today's prompts from Write Better Poetry and NaPoWriMo: (1) Write a poem that incorporates one or more prime numbers, and (2) write a one-stanza poem in the form of a letter to someone famous (real or fictional) or to yourself, and a one-stanza response.

I started thinking about prime numbers and looked for who might have discovered them. Though that discovery seems lost in antiquity (there is evidence the ancient Egyptians fiddled with them), the ancient Greek polymath Eratosthenes (er-a-TOS-the-neez) of Cyrene (an area now part of Libya), who lived in the 3rd Century B.C., is credited with devising a method for finding them in a sequence of numbers. It's called the Sieve of Eratosthenes, and it's basically a numbered grid that is ten cells wide and as long as you want to make it. By crossing out or eliminating all the non-prime, or composite, numbers on the grid (by multiplying by 2, 3, 5, 7, etc.), the cells that are left are the prime numbers. In other words, they "fall through the sieve." Here's an animated example of how it works. Eratosthenes is actually most well known as the first person to accurately estimate the circumference of the Earth. I imagined a letter to him from an appreciative "fan" and his response. I was thinking of the clerihew verse form (a four-line humorous rhyming poem about a famous person that begins with their name), although this probably isn't technically a clerihew. Also, note that the year in the title is a prime number.

Fan Letter, 223 B.C.
 
Eratosthenes, you are so smart -
this letter comes straight from the heart.
It's amazing, I think, that you give
us prime numbers that fall through your sieve.
 
Well, thanks! You know, chances were teeny
that your letter'd reach me in Cyrene.
Now excuse me while I prove my worth
by measuring the girth of the Earth.