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  • Fibonacci's 1202 manuscript "Liber Abaci," the foundation of modern arithmetic, contains a number of magic tricks, including several versions of the famous three-object divination, wherein a spectator mentally selects one of three objects and the magician correctly identifies the spectator's choice.

    Pick a Card, Any Card

  • More than any other book, the Liber Abaci introduced the Indian system to the West.


  • Professional abacus operators felt threatened by the easier method, for one thing, and the timing of publication was not perfect: the Liber Abaci appeared during the period of crusades against Islam, with the clergy suspicious of anything with Arab connotations.


  • Realizing that they were much better than Roman numerals, Fibonacci wrote a book about the decimal place value system called the Liber Abaci, published in 1202.


  • The Mathematician Leonardo of Pisa, more commonly known as Fibonacci, wrote a book called Liber Abaci, The Book of Abacus, in 1202.

    Archive 2007-03-01

  • He used what is now known as the Fibonacci sequence - actually a pre-6th-century Indian concept - as an example in his famous and apparently brilliant book about math, Liber Abaci, or Book of Calculation, which is why we have it now.

    Archive 2007-09-01

  • Corporate Connections: Abaci aren't as popular as they once were, but you can still buy one from companies like American Science and Surplus or Advance Engineering.

    No. 2 The Abacus

  • Abaci are still widely used in the East, with slight variations in design--such as the number of beads and wires, and the presence of dividing beams--occurring between countries.

    No. 2 The Abacus

  • [534] "Incipit liber Abaci a Leonardo filio Bonacci compositus anno 1202 et correctus ab eodem anno 1228."

    The Hindu-Arabic Numerals

  • Peter Abaci, M.D. Chronic pain specialist published a call to action for a "cultural transformation in the way clinicians and the public view pain and its treatment."

    The Full Feed from

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