Go To Image Magick. On the first page using the "Format" drop-down menu, select Pattern.
Leave the "Size" box empty. If there's already a width and height parameter in the "Size" box, delete that parameter, so the "Size" box will be empty.
In the "Meta" box type in hexagons.
In the "Scene" box type in a width and height parameter. Let's make it 640W X 480H. Don't forget. You need to place an exclamation point after the height parameter. So, in the "Scene" box enter 640x480!
Scroll up the page and click the View link to see the result.