30: Difference between revisions

From Number
Line 13: Line 13:
|-
|-
| [[Giuga number]]: composite number <math>n</math> such that <math>p</math> divides <math>(n/p) - 1</math> for all prime divisors <math>p</math> of <math>n</math>. || first Giuga number || {{#lst:Giuga number|list}} || check on each prime divisor:<br>2 divides (30/2) - 1 = 14<br>3 divides (30/3) - 1 = 9<br>5 divides 30/5 - 1 = 5
| [[Giuga number]]: composite number <math>n</math> such that <math>p</math> divides <math>(n/p) - 1</math> for all prime divisors <math>p</math> of <math>n</math>. || first Giuga number || {{#lst:Giuga number|list}} || check on each prime divisor:<br>2 divides (30/2) - 1 = 14<br>3 divides (30/3) - 1 = 9<br>5 divides 30/5 - 1 = 5
|-
| [[primorial]]: product of the first few prime numbers || third primorial: product of the first three prime numbers || {{#lst:primorial|list}} || The first three primes are 2,3,5, and their product is 30.
|}
|}

Revision as of 01:01, 23 June 2012

This article is about a particular natural number.|View all articles on particular natural numbers

Summary

Factorization

The factorization is as follows, with factors 2, 3, and 5:

30=213151=235

Property or family Parameter values First few members of the family Proof of satisfaction/membership/containment
Giuga number: composite number n such that p divides (n/p)1 for all prime divisors p of n. first Giuga number 30, 858, 1722, 66198, [SHOW MORE]View list on OEIS check on each prime divisor:
2 divides (30/2) - 1 = 14
3 divides (30/3) - 1 = 9
5 divides 30/5 - 1 = 5
primorial: product of the first few prime numbers third primorial: product of the first three prime numbers 1, 2, 6, 30, 210, 2310 View list on OEIS The first three primes are 2,3,5, and their product is 30.