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

In this case, that meant pulling from both algebraic number theory and discrete geometry, which have about as much in common as the marathon and pole vault.

From The Wall Street Journal • May 30, 2026

Now they are solving classic problems in combinatorial geometry using algebraic number theory.

From The Wall Street Journal • May 30, 2026

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

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