Difference between revisions of "Deficient number"

(Blanked the page)
m (Problems)
 
(5 intermediate revisions by 3 users not shown)
Line 1: Line 1:
 +
A '''Deficient number''' is a number <math>n</math> for which the sum of <math>n</math>'s [[proper divisor|proper factors]] is less than <math>n</math>. For example, 22 is deficient because its [[proper divisor|proper factors]] sum to 14 < 22. The smallest deficient numbers are 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 16, and 17.
  
 +
==Problems==
 +
===Introductory===
 +
====Problem 1====
 +
Prove that all [[prime number|prime numbers]] are deficient.
 +
 +
[[Deficient number/Introductory Problem 1|Solution]]
 +
 +
====Problem 2====
 +
Prove that all [[perfect power|powers]] of [[prime number|prime numbers]] are deficient.
 +
 +
[[Deficient number/Introductory Problem 2|Solution]]
 +
 +
==See Also==
 +
[[Perfect number]]
 +
 +
[[Abundant number]]

Latest revision as of 11:39, 9 February 2018

A Deficient number is a number $n$ for which the sum of $n$'s proper factors is less than $n$. For example, 22 is deficient because its proper factors sum to 14 < 22. The smallest deficient numbers are 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 16, and 17.

Problems

Introductory

Problem 1

Prove that all prime numbers are deficient.

Solution

Problem 2

Prove that all powers of prime numbers are deficient.

Solution

See Also

Perfect number

Abundant number