perplexus.info :: Just Math : Quarting the cube

Quarting the cube (Posted on 2013-02-28)

Select integer x and triangular number y such that 8y=3x^4-2x^2-1.

Prove that y is divisible by 28 - or find a counter-example.

See The Solution Submitted by broll

Rating: 5.0000 (2 votes)

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

re(2): SOLUTION +some add-ons

Comment 6 of 6 |

Mr Broll, Esq

It is implicit indeed, but passed unnoticed.

I liked this problem very much - it forced me to go down the memory lane all the way to Recursion Avenue..

Cheers!

Posted by Ady TZIDON on 2013-03-02 07:25:51

Please log in:

Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (5)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:


perplexus dot info