A very short story (not quite two pages) about an insecure mathematician:
(quoted from A House for Living)
The mathematician moves into a glass condominium with fourteen doors and has nightmares about the rooms behind them switching places. Sometimes she opens them to find a rival mathematician sitting on a long velvet couch. The rival has a retentive memory and a svelte build, while the mathematician has neither.

The mathematician is eccentric and makes odd choices:
(quoted from A House for Living)
The mathematician redesigns her staircase so that some steps are very tall and some very short. She supposes this will help exercise her heart, but grows accustomed to the patterns rather quickly and starts tripping down traditional staircases at work. Whenever this happens, the rival always happens to be walking by, eating radishes.

Other strange things in the story either suggest that it takes place in a surreal fictional universe or that the character is going insane:
(quoted from A House for Living)
One morning she touches her head, which throbs, and finds a murky residue. On the pillow beside her is a gray lump, translucent like a cube of gelatin. The mathematician prods it and notices an odor similar to talcum powder. Beneath it is a small stain that is impossible to wash out. Perplexed, she keeps the lump in a glass jar in the refrigerator.

Why is the main character a mathematician? Occasionally she is described as doing math ("She'll...go to the computer to compute something untenable"), but unless I am misinterpreting it, I believe that this story is both a product and a source of the prejudice that mathematicians are neurotic and mentally unstable. Even though I like the terse writing style and find the plot entertainingly bizarre, that tired stereotype keeps me from really being able to recommend this as a work of mathematical fiction.
