Finding the rule for the pattern
This task is about writing rules for spatial patterns.
a) 


Shape 1  Shape 2  Shape 3  Shape 4 


d_{n} = __________________ 
d_{n} is the number of dots in shape n,
n is the shape number. 
b) 


Shape 1  Shape 2  Shape 3  Shape 4 


l_{n} = __________________ 
l_{n} is the number of straight lines in shape n,
n is the shape number. 
c) 


Shape 1  Shape 2  Shape 3  Shape 4 


s_{n} = __________________ 
s_{n} is the number of crosses in shape n, 