All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Just Math
Even and odd powers (Posted on 2005-02-09) Difficulty: 4 of 5
Let [z] mean the Greatest Integer less than or equal to z. Find a positive real number X, such that [X^n] is an even number whenever n is even, and [X^n] is an odd number whenever n is odd.

See The Solution Submitted by SteveH    
Rating: 4.2222 (9 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
re: Uncle! | Comment 16 of 23 |
(In reply to Uncle! by McWorter)

I give up, too.

I also have ben playing with David Shin's proof outline, and I have convinced myself that it was a brilliant idea that doesn't work.  If we are focusing on the positive root of ax^2 + bx + c = 0,  then I believe that a must equal one, in order to ensure that X(n) is always an even integer. 
However, I have ruled out:
a = 1, b even, c even
a = 1, b even, c odd
a = 1, b odd, c even
a = 1, b odd, c odd

I'll be very interested to see the solution.  I have also come around to thinking (despite what SteveH says) that the problem maybe should be:  "Find a positive real number X, such that [X^n] is an even number whenever n is odd, and [X^n] is an odd number whenever n is even."

Incidentally, SteveH and I are not the same person, not relatives, not collaborators, and (to the best of my knowledge) not even acquaintances.

  Posted by Steve Herman on 2005-03-03 17:39:18

Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (3)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2024 by Animus Pactum Consulting. All rights reserved. Privacy Information