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

Home > Just Math
Supreme Subset (Posted on 2014-01-02) Difficulty: 3 of 5
Let us define the set T = {1,2,3,...,700}. Now, S is a subset of T such that no two numbers in S differ by a difference of 2 or 5.

Determine the largest number of elements that S can have.

No Solution Yet Submitted by K Sengupta    
No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
Some Thoughts Blindly crossing possible solution | Comment 4 of 6 |
Write down the numbers and starting at 1 consider if each number can be kept or discarded you get the sequence of remaining numbers:
1,2,5, 8,9,12, 15,16,19
which is a cycle of length 7 of which 3 remain.
3/7 or 700 = 300

I don't know if this can be improved.

  Posted by Jer on 2014-01-02 15:04:41
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 (5)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2017 by Animus Pactum Consulting. All rights reserved. Privacy Information