Poetry with mathematical symbols

On the internet and elsewhere a variety of viewpoints are expressed about the criteria poetry should satisfy to be "mathematical." Today I want to introduce samples and links for three writers:   Bob Grumman (Florida), Gregory Vincent St Thomasino (New York), and Kaz Maslanka (California).  Grumman and Maslanka write poems with a strong visual element and, as the blogs and comments for all three testify, they differ in their views of what may be properly called "mathematical" poetry..