
 Maya Mathematics, simple and ingenious. Fast to learn, easy as a game. 
  Just as the decimal system goes by 1, 10, 100, 1000, 10000, etc., the Maya vigesimal system goes 1, 20, 400, 8000, 160000, etc. While in the decimal system there are ten possible digits for each placeholder [0  9], in the Maya vigesimal system each placeholder has a possible twenty digits [0  19]. 
  When written horizontally, the bars are placed vertically and the dots go to their left and higher vigesimal positions grow to the left of the first entry. 
  Thus when writing vertically the vigesimal positioning system, to write 20 a zero is placed in the first position (base) with a dot on top of it, in the second position. 
 www.mayacalendar.com /mayamath.html (494 words) 
