Ideal numbers are a set of numbers that have special properties.

Motzkin numbers are a sequence of numbers that appear in combinatorial mathematics.

Delannoy numbers are a sequence of numbers that count the number of paths from one corner of a grid to another corner, moving only right, up, or diagonally.

Narayana numbers are a sequence of integers that appear in combinatorial mathematics.

Schröder numbers are a sequence of integers that count various combinatorial objects.

Lychrel numbers are a fascinating mathematical concept.

There are several negative numbers in the data set.

I have several positive numbers in my bank account.

Superabundant numbers are integers that have more divisors than any of their smaller positive integers.

The library has a wide variety of book numbers.