Reading package lists...
Building dependency tree...
Reading state information...
Package xserver is a virtual package provided by:
  xvfb:i386 2:1.15.1-0ubuntu2.7
  xserver-xephyr-lts-vivid 2:1.17.1-0ubuntu3.1~trusty1
  xserver-xephyr-lts-utopic 2:1.16.0-1ubuntu1.2~trusty2
  xserver-xephyr 2:1.15.1-0ubuntu2.7
  xnest 2:1.15.1-0ubuntu2.7
  vnc4server 4.1.1+xorg4.3.0-37ubuntu5.0.2
  xvfb 2:1.15.1-0ubuntu2.7
  xserver-xorg-lts-vivid 1:7.7+7ubuntu3~trusty1
  xserver-xorg-lts-utopic 1:7.7+7ubuntu2~trusty1
  xserver-xorg 1:7.7+1ubuntu8.1
  tightvncserver 1.3.9-6.4ubuntu1