{Yep, I know; This post's subject, doesn't match the content. Just thought I'd 'throw' one of my never seen before 'screwballs'} -
 
A WEEK IN THE LIFE OF A MATHEMATICIAN /by Ken Falconer
 
 
’Twas on a Monday morning I had a bright idea,
I was lying in the bath tub and the strategy seemed clear,
For a problem posed by Erdös back in nineteen forty nine,
On sequences dilated into subsets of the line.
 
’Twas on a Tuesday morning I jotted down my thoughts,
I covered backs of envelopes with surds and aleph noughts.
After several cups of coffee I began to feel inspired,
And a lengthy calculation gave the answer I desired.
 
’Twas on a Wednesday morning I wrote the details out.
My lemmas and corollaries left little room for doubt.
I filled up many pages just to get the logic right,
And with epsilons and deltas I made it watertight.
 
’Twas on a Thursday morning I typed the paper up,
With ’slash subset’ and ’slash mapsto’ to say nothing of ’slash cup’.
My LaTeXing was perfect, printed out it looked so good,
Should I send it to the Annals? I rather thought I would!
 
’Twas on a Friday morning I read the paper through,
I checked out every detail as good authors ought to do.
At the bottom of page twenty in an integral I found,
I’d divided through by zero and the proof crashed to the ground.
 
On Saturday and Sunday I was too depressed to care,
So ’twas on a Monday morning that I had my next idea.