Sun, 15 Apr 2018
The earliest known mathematics book printed in Europe is an untitled arithmetic text published in Treviso in 1478, Originally written in Venetian dialect.
The Treviso Arithmetic states unequivocally:
And a little later:
(English translations are from David Eugene Smith, A Source Book in Mathematics (1959). A complete translation appears in Frank J. Swetz, Capitalism and Arithmetic The New Math of the Fifteenth Century (1987).)
By the way, today is the 311th birthday of Leonhard Euler.