In volume 4 of The World of Mathematics (James R Newman, Editor; Dover 2003), in a section entitled "Amusements, Puzzles, and Fancies," is an essay by Edward Kasner and James R. Newman entitled "Pastimes of Past and Present Times." This piece is prefaced by a quote from Mark Twain: "Work consists of whatever a body is obliged to do, and play consists of whatever a body is not obliged to do." One of the characteristics that mathematicians and poets have in common is that both enjoy mind-play -- mental adventures with ideas or numbers or words, dancing and shaping into some new thing.
Two of the puzzles in the Kasner-Newman essay are posed as poems; I offer them below.
First (by the Scottish mathematician Alexander Macfarlane), this jingle:
Brothers and sisters have I none,
But this man's father is my father's son.
This second verse-puzzle is said to have been found on an old gravestone at Alencourt, near Paris:
Here lies the son; here lies the mother;
Here lies the daughter; here lies the father;
Here lies the sister; here lies the brother;
Here lies the wife and the husband.
Still, there are only three people here.
To solve this latter puzzle I needed to use the idea "any woman is a daughter/any man is a son." Furthermore, my solution arrangement of family members turned out to be incestuous. Maybe you can do better.
For a poem about The World of Mathematics, see my 22 March 2011 posting.