perplexus.info :: Numbers : Listing cubes

Home > Numbers

Listing cubes (Posted on 2013-10-01)

List all integers n, below 10000, such that 12*(n^2 + 2) is a perfect cube.

No Solution Yet Submitted by Ady TZIDON

Rating: 4.5000 (2 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)

re: A start - small hint.

| Comment 2 of 3 |

(In reply to A start by Jer)

a. Since n appears only in an even power i.e. n^2, both positive and negative integers qualify.

b.It is much easier to get all the answers once you

understand that (n^2+2) must equal 18*k^3.

Just continue from here - you will not be "stuck"- just evaluate n for k=1, 2 etc.

Posted by Ady TZIDON on 2013-10-01 15:07:04

Please log in:

Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (15)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:


perplexus dot info