Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

A permutation with a special property question!

  1. May 27, 2009 #1
    Hi there,
    i was wondering if you had any thoughts on the following question:

    Let [tex](a_{1}, a_{2}, ..., a_{2n})[/tex] be a permutation of [tex]{1, 2, ..., 2n}[/tex] so that [tex]|a_{i} - a_{i+1}| \neq |a_{j} - a_{j+1}| [/tex], whenever [tex] i \neq j [/tex].

    Show that [tex]a_{1} = a_{2n} + n[/tex], if [tex] 1 \leq a_{2i} \leq n [/tex] for [tex]i = 1,2, ..., n[/tex]
     
    Last edited: May 27, 2009
  2. jcsd
  3. May 29, 2009 #2
    still no ideas??
     
  4. May 29, 2009 #3
    According to my calculations (proof) it's not possible.. Try proving this..
     
    Last edited: May 29, 2009
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: A permutation with a special property question!
Loading...