If you like this blog, then you either are or should be a fan of the late Martin Gardner, the long-time “Mathematical Games” columnist for Scientific American. On the 21st of October (what would have been Gardner’s 96th birthday), “Gatherings for Gardner” will take place around the world, where fans can share their favorite puzzles, ideas, magic tricks and reminiscences in what’s being billed as a global “celebration of mind”. You’re welcome to attend one of these events — or to host one.

(Potential attendees would surely benefit from a list of locations in lieu of having to navigate that idiotic map, but that’s what’s there.)

It was at a previous Gathering for Gardner that puzzle designer Gary Foshee posed his notoriously tricky probability puzzle about the mom with a son born on a Tuesday. (Spoilers here.) If you host or attend a gathering, do come back here and share your favorite finds.