200332
It is usually phrased in terms of the fixed point iteration : Given iterates x_1 , x_2 , ... , x_k in \ Bbb R ^ n , one constructs the n \ times ( k-1 ) matrix U = ( x_2-x_1 , x_3-x_2 , ... , x_k-x _ ) whose columns are the k-1 differences .
 None
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 None