code: @Override
      public String parameters() {
          FllExporter exporter = new FllExporter();
          StringBuilder result = new StringBuilder();
          result.append(String.format("%s %s %s",
                  Op.str(minimum), Op.str(maximum),
                  exporter.toString(aggregation)));
          for (Term term : terms) {
              result.append(" ").append(exporter.toString(term));
          }
          return result.toString();
      }
docs: Returns the parameters of the term
  
  @return `"aggregation minimum maximum terms"`