# How many good words are there?

A “good” word is any seven letter word consisting of letters from $\{A,B,C\}$ (some letters may be absent and some letter can be present more than once), with the restriction that $A$ cannot be followed by $B$, $B$ cannot be followed by $C$, and $C$ cannot be followed by $A$. How many good words are there?

I could find out $36$ good words. Is that the true answer?

You can choose the first letter in $3$ ways and any of the other letters in $2$ ways, so there can be $3*2^6=192$ good words