though they meant geometric series

Maybe that has a cultural aspect. Here in Germany the equation x² - y² = (x - y)(x + y) is known as the "third binomial formula" with a generalization to the n-th power as cited.

Greetings,
-jo

$gryYup$d0ylprbpriprrYpkJl2xyl~rzg??P~5lp2hyl0p$

In reply to Re^2: [OT] math fulguration by jo37
in thread [OT] math fulguration by Discipulus

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