The numeral system employed, known as algorism, is positionaldecimal notation.
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Algorism comprises all of the rules for performing arithmetic computations using this type of written numeral.
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This study is sometimes known as algorism.
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But all this even, and the algorism, as well as the art of Pythagoras, I considered as almost a mistake in respect to the method of the Hindus.
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The Arabic (or decimal) system of numeration
Computation with Arabic figures
Algorism is the technique of performing basic arithmetic by writing numbers in place value form and applying a set of memorized rules and facts to the digits. One who practices algorism is known as an algorist. ...
Obsolete spelling of algorithm; Computing in, or using, Arabic numerals
Eponym: use of the Arabic number system (rather than, say, Roman numerals)
N. - art of calculating, especially in Arabic numeration; arithmetic. algorismic, adj.