I made an Ulam Spiral generator. Download:
http://www.cemetech.net/programs/index.php?mode=file&id=882
It works on both the color and non-color calcs. Here are some screen shots:
Many thanks to Weregoose for math help
http://www.cemetech.net/programs/index.php?mode=file&id=882
It works on both the color and non-color calcs. Here are some screen shots:


Many thanks to Weregoose for math help
