number theory

American  

noun

Mathematics.

1. the study of integers and their relation to one another.

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number theory British  

noun

1. the study of integers, their properties, and the relationship between integers

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Etymology

Origin of number theory

First recorded in 1910–15

Example Sentences

There was some bullish RSI divergence with a higher RSI low in early and late February while price made a lower low, and notice how round number theory came into play.

From Barron's • May 4, 2026

The tide didn’t begin to turn until Feb. 6, when price action staged a near-textbook defense of the $60,000 level, reinforcing round number theory.

From Barron's • Apr. 22, 2026

Notice how round number theory played a role early on with a bearish shooting star on June 23 at the $300 level.

From Barron's • Apr. 14, 2026

Peering at Broadcom’s daily chart, the stock has traded between the $300 and $400 figures since early last September, influenced by round number theory.

From Barron's • Apr. 13, 2026

A strong streak of romanticism runs through mathematics, manifesting itself most clearly in the most fundamental areas of mathematics, number theory and logic.

From "Innumeracy: Mathematical Illiteracy and Its Consequences" by John Allen Paulos