Block occurrences [in rule 30]
The pictures below show at which step each successive block of length up to 8 first appears in evolution according to various cellular automaton rules starting from a single black cell. For rule 30, the numbers of steps needed for each block of lengths 1 through 10 to appear at least once is {1, 2, 4, 12, 22, 24, 33, 59, 69, 113}. (See also page 871.)
![Block occurrences [in rule 30] image 1](/nks/notes/notes-12-3--block-occurrences-in-rule-30/fig-a.png)