It was 1968, one evening at the YMCA in New Delhi. Three mathematics students, a physicist and a chemist were talking. An innocuous topic led them to mathematics: on the city's sports fields, people played football with a traditional ball, while the whole of Europe had switched to a ball made of hexagons and pentagons. Like good scientists, the students assumed that this structure provided a closer approximation to the ideal shape of a sphere. But before they could say more, they first needed to know how many hexagons and pentagons made up the ball. None of them had ever thought to examine a football closely… "I'll calculate it," said one of the mathematicians. "Are you crazy? That's impossible!" another replied. "Not at all—with Euler's formula…"
The traditional ball in the 1960s. The new European ball.
Pentagons and hexagons
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