Customized version of http://www.thingiverse.com/thing:270130

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=270130

Set the infill to 0%. Stop the 3D print at 91% if you don't want a solid cover on top the vase. No supports are needed.

Using the following options:

slice_layers = 4
vase_height = 80
number_of_sides = 8
top_radius = 40
top_rotation = 180
bottom_radius = 25