[Arjen Markus] (18 december 2003) I am mildly proud to present a first (underdocumented) version of a ''mathematical notebook''. 

After at least 10000 seconds of hard labour, meticulous programming and self-defying testing, it works! I had to use the most cunning techniques I could muster:   
   * pre-coding design phase (meaning I wrote some scribbles on a piece of paper on the way home)
   * rapid application development (meaning I was anxious to see it grow, so I ran it as soon as something could show up)
   * code reuse by multiple copy-paste-edit cycles (I hardly ever start from scratch, but simply copy an existing file into a new directory)
   * visual testing (meaning I tried to see that it did what I wanted it to do)

This was all needed to meet my deadline: the end of the evening.

But I did it! 

Below you will find the first fruits of this herculean achievement. Enjoy!

Okay, what is it? 

Note