The Hindu-Arabic numbering system is introduced to the West by Italian mathematician Fibonacci in his book Liber Abaci, which also contains chapter about sequence known today as Fibonacci number


Republic of Pisa


Very important (8)




As my father was a public official away from our homeland in the Bugia customshouse established for the Pisan merchants who frequently gathered there, he had me in my youth brought to him, looking to find for me a useful and comfortable future; there he wanted me to be in the study of mathematics and to be taught for some days. There from a marvelous instruction in the art of the nine Indian figures, the introduction and knowledge of the art pleased me so much above all else, and I learnt from them, whoever was learned in it, from nearby Egypt, Syria, Greece, Sicily and Provence [...] If, by chance, something less or more proper or necessary I omitted, your indulgence for me is entreated, as there is no one who is without fault, and in all things is altogether circumspect. The nine Indian figures are: 9 8 7 6 5 4 3 2 1 With these nine figures, and with the sign 0 which the Arabs call zephir any number whatsoever is written.

Liber Abaci by Fibonacci