Identity of a Mathematician Mentioned in Euler

The identity of Sauwerii can be found in a footnote of a publication of the first part of Commentationes arithmeticae. Specifically, here.

Euler is referring to a Joseph Sauveur, 1653-1716. More specifically, he is referring to Sauveur's paper Construction generale des quarres magiques (accents omitted), which appeared in Mem. de l'acad. d. sc. de Paris [academy of sciences of Paris], 1710, p. 92.

There is also a reference to Sauveur in Sandifer's book, "The Early Mathematics of Leonhard Euler", in the chapter about E-36.

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