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

The weekly chart illustrates how round number theory came into play at the $200 figure:

From Barron's • Apr. 24, 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

Looking at AAL’s monthly chart one can see how round number theory has come into play at the $10 figure:

From Barron's • Apr. 8, 2026

Round number theory then came into play at $30 with a bearish shooting star candle on March 19.

From Barron's • Mar. 31, 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