Step-by-step explanation:
[tex]b(1) = 4[/tex]
Since this is an arithmetic sequence, notice that if you subtract b(1) (i.e., 4) from b(2)(i.e., 22), you get 18. Likewise, if you subtract b(2) from b(3) you also get 18. Therefore,
[tex]b(n) = b(n-1) + 18[/tex]
