In number theory, a frugal number is a natural number in a given number base that has more digits than the number of digits in its prime factorization...

Frugal innovation or frugal engineering is the process of reducing the complexity and cost of a good and its production. Usually this refers to removing...

In number theory, a perfect number is a positive integer that is equal to the sum of its positive proper divisors, that is, divisors excluding the number...

the number 1 differently than larger numbers, sometimes even not as a number at all. Euclid, for example, defined a unit first and then a number as a...

A k-powersmooth number has all pm ≤ k where p is a prime factor with multiplicity m. A frugal number has more digits than the number of digits in its...

A composite number is a positive integer that can be formed by multiplying two smaller positive integers. Equivalently, it is a positive integer that has...

numbers in any base. A number that is either equidigital or frugal is said to be economical. Let b > 1 {\displaystyle b>1} be the number base, and let K b...

In mathematics, the Fibonacci sequence is a sequence in which each number is the sum of the two preceding ones. Numbers that are part of the Fibonacci...

In number theory, a weird number is a natural number that is abundant but not semiperfect. In other words, the sum of the proper divisors (divisors including...

A prime number (or a prime) is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that...