What Causes Crystals Structure?

• triangle - ecktransversalen
  the sides of a triangle ABC are in sequence in the ratio 1:3 (2:3) split and connected to the opposite corner. how big is formed in the inner triangle (in relation to the whole triangle)? problem is to
  
a number of species are various so-divided into two three terms, that the respective sum of squares is also consistent -
• 
  pay three.
• 7/3-System
  can be any whole number, eg in a given system. 10 or 2 or 8 or 16-system representation. how it looks when you for example a whole number in a fraction system. will represent the 7/3-system:
  20 shall be turned into 7/3-system