select problem!!!

From: C#User (someone_at_yahoo.com)
Date: 04/21/04 

Date: Wed, 21 Apr 2004 12:34:05 -0400

hi,
  i have a table like below:
pk V
1 1
2 2
3 3
4 4
5 2
6 2
7 1
8 4

I want to pick out pk 3,6,7,8 because they are the latest happening of the
1,2,3,4. How can i accomplish this?

I appreciate your help!