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

Round number theory came into play at the $100 figure with a bearish shooting star on Sept. 22, followed by a bearish dark cloud cover and two bearish engulfing candles in October.

From Barron's • May 7, 2026

Looking at the stock’s daily chart one can see how round number theory came into play at the very round $100 figure:

From Barron's • Apr. 20, 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