Changes

Changes made August 2, 1997:

Figure V3a.gif on the VennWhatEJC.html page was corrected. The old version had the green curve drawn incorrectly as two curves. Thanks to Prof. Peng Yee Hock of the Mathematics Department of the University of Malaysia for pointing out this error.
"Caius College" changed to "Gonville and Caius College" at the suggestion of Prof. Keith Briggs of the Dept of Plant Sciences at Cambridge University. Also "Humberside" changed to "Yorkshire".

Changes made December 23, 1997:

HTML fix-up. Added some quotes around file names and parameter values. Added HEIGHT and WIDTH parameters to images.

Changes made March-May 1998:

Updated the open problem page. Thanks to Branko Grünbaum for pointing out an error in the earlier version.
Added material on minimum vertex Venn diagrams on the "Graphs associated with..." page.
Re-arranged some of the material on the pages VennGraphEJC.html and VennSymmEJC.html.
Added definition of rigid Venn diagrams to the VennGraphEJC.html page.
Added results about symmetric Venn diagrams for n = 5, summarizing the results of an exhaustive computer search done by Stirling Chow and F.R, including howcirc.gif which had been sent to some colleagues in postscript form on Halloween day 1996.
Added an animated Victoria to the page on symmetric diagrams. Hit the stop button if it's driving you crazy!
Added a few new references, including Peter Hamburger's survey article. Updated some references.
Added De Bruijn cycle Venn diagram example at bottom of VennOtherEJC.html.

Changes made August-September 1998:

Changes made February 1999:

Changes made February 2001:

This was a major updating, in preparation for a new version to appear as an on-line survey in the ElJC. Not all changes are outlined below.

Added the references [Gr99], [Ca99],
Added the page VennTriangleEJC.html, with a link to it from VennOtherEJC.html,
Removed the open problem that the above page solved.
Added the page VennSymm11EJC.html, with a link to it from the new material on Peter Hamburger's 11-Venn diagram on the page VennSymmEJC.html.
Added new open problems about quadrilaterals.
Added Tutte embeddings and Tutte embeddings with one curve colored green of all the 6+17 = 23 symmetric simple 7-Venn diagrams.
Added renderings of the simple 7-Venn diagrams as a links (collections of knots -- or unknots in this case). These were produced with Robert Glenn Scharein's KnotPlot program, using coordinates that were computed by Chelsea Jones.

File Structure