# All strings that contain no run of a’s of length greater than two for \$Sigma = {a,b,c}\$

The solution to this problem is $$(b + c)^*+(b + c)^*((a + aa)(b + c)^+)^*(a + aa)(b + c)^*$$
Isn’t the $$+$$ sign an union between sets?, I am asking because I am viewing the line $$(b + c)^*+(b + c)^*$$
as $$AUA$$ which is $$A$$ so I do not see a reason to repeat the same set. Thanks in advance.