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34

Using the following command I was able to get the text centered on the screen in the color green. It says GREEN x32.

Serial2.write("\x00\x00\x00\x00\x00\x01Z00\x02""AA\x1B\x20\x62\x1C\x32", 18);
      Serial2.print("GREEN x32!");
      Serial2.write("\x04");

I don't understand what the 18 is supposed to do. Can someone explain to me what that is for?