Tuesday, October 21, 2025
– Live Presentation with
Peter Renz –
Session at 12 Noon Atlanta time
(check your time here)
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After this virtual CoM presentation on Zoom, we will meet for an informal social session in a different Zoom space where we can all see each other (see the blue button below). That Zoom meeting will start around 1pm ET.
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Mathematical Games: Works in ProgressMartin Gardner’s columns and books amused and interested readers – turning many into doers. The doers contributed to his columns and books and to mathematics to this day. You can see these contributions on the 2005 CD of the Mathematical Games books and by searching on the Web.How could a magician predict the sum of an audience-chosen set of five numbers? Read the answer in “Magic “with a Matrix” the1340 word column for January 1957. This “force” lies in the matrix shown below. You find matrices like this on calendars and elsewhere. They are easy to cook up. Martin tells how magicians use them in routines. One reader pointed out how to create birthday cards that sum to a friend’s age.There are mathematical aspects to this story, but Martin heads us in the right direction without getting bogged in details – then reports on developments. This is work in progress best understood starting with the original columns, so brief and effective. I will show how this is, using columns covered in the second editions of his first four books.Below is the forcing matrix from January 1957. How was it created? The amorous bugs each crawling directly toward its adored mate. How far do they crawl before they collide? And Sam Loyd’s “white to move and mate in 3” chess problem, whose solution is more difficult than you may imagine.
Peter L. Renz became Martin Gardner’s editor at W. H. Freeman and Company in 1974. He worked with him on and off until Martin’s death. He arranged putting the 15 Mathematical Games books in digital form and worked on second editions with Martin. He taught mathematics at Reed, Wellesley, and Bard Colleges, and he hiked and climbed in the wilds of Western Canada, Argentina, and Nepal.