How many proteins are associated with an institution in a building with at least 20 floors?
return institutions ;return buildings of  #1 ;return floors of  #2 ;return number of  #3 for each  #1 ;return #1 where  #4 is higher than 20 ;return protein associated with  #5 ;return number of  #6
['select', 'project', 'project', 'group', 'comparative', 'project', 'aggregate']