The Title of the talk was: How to compute Pi by tossing a coin.
Welcome Attendance Quiz (w/o answers)
All the posted answers were good, but the lucky winner (of Richard Stanley's book `Catalan Numbers') is Jakub Stepo
Farewell Attendance Quiz (w/o answers)
All the posted answers were good, but the lucky winner (of Richard Stanley's book `Catalan Numbers') is John Wu (Princeton University)
Challenges: So far my computer (see the above web-page) was only able to find the polynomial describing the number of ways n teams can all play each other and each get r Goals For and r Goals against, for 1 ≤ n ≤ 6. I am pledging to donate 100 dollars to the OEIS in honor of the first person to do it for seven teams, and an additional 200 dollars for eight teams.
Added Sept. 7, 2026:
Guoce Xin and his former grad student, Zihao Zhang, met this challenge,
and independently, Gabe Vandevere also also met this challenge.
A donation to the OEIS in their honor was made. See here (and do ^F for Vandervere or Guoce or Zihao)
Added Sept. 23, 2026: Read this fascinating paper by Xinru Jiang, Guoce Xin, Cheng Zhang, and Yueming Zhong. That goes way beyond.