**Webinar on The Case of a Mysterious Triangle**

The Webinar on The Case of a Mysterious Triangle took place on Friday, July 16th, 2021 from 5 pm until 6 pm, with Dr. Eduardo Mancera, Vice President of the Interamerican Committee on Math Education (CIAEM), as our invited speaker. This virtual event was free and open to the general public.

The invited speaker presented many mathematical curiosities about the famous Pascal’s triangle. Dr. Eduardo Mancera showed how the natural numbers, the prime numbers, the squares of the natural numbers, the consecutive powers of 2, the consecutive powers of 11, the number pi, the triangular numbers, the Fibonacci numbers and the golden ratio appear in Pascal’s triangle. The speaker also explained the connection between Sierpinski’s triangles and Pascal’s triangle and described David Singmaster’s conjecture about Pascal’s triangle. This virtual event was co-organized with the Mexican Association of Educational Mathematics (AMME).