Monday

April 21, 2014

April 21, 2014

Posted by **Andy** on Thursday, December 23, 2010 at 2:36am.

- math -
**drwls**, Thursday, December 23, 2010 at 3:52amYes, it is true.

All PRIME numbers above 3 are of the form 6n − 1 or 6n + 1, because all other numbers are divisible by 2 or 3.

That is, the other numbers above 3 (that cannot be written as 6n-1 or 6n+1) can be written 6n, 6n+2, 6n+3, or 6n+4. All of those are divisible by 2 or 3 and therefore cannot be prime.

(6n+5 can be written 6(n+1)-1 where n+1 is the next integer)

**Related Questions**

math 213 #18 - A student claims that every prime greater than 3 is a term in the...

Mathematics : Arithmetic Sequence - The 5th term and the 8th term of an ...

math - Find the 265th term of an arithmetic sequence whose second term is 5/8 ...

math - find the 4th term of an arithmetic sequence whose first term is -8 and ...

Math - A sequence is formed by adding together the corresponding terms of a ...

arithmetic - Find the sum of the first 25 terms of an arithmetic sequence whose ...

math - find the rule for the Nth term of the arithmetic sequence. 11/2, 25/6, 17...

Maths - 1..The first 2 terms of a geometric progression are the same as the ...

math - 1. Use the given arithmetic sequence to answer the following problems. ...

Arithmetic Sequence - Given the third term of an arithmetic sequence less than ...