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

Looking at Palantir’s chart, round number theory came into play at the $200 level with only two closes above that figure on Oct.

From Barron's • May 7, 2026

Looking at its daily chart shows how round number theory has come into play at the $300 figure.

From Barron's • Apr. 16, 2026

Round number theory has come into play here as the price broke above a bear flag right at the $100 level this week.

From Barron's • Apr. 15, 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