What is the meaning of $i$ in $(b_n \quad b_{n-1} \quad \cdots \quad b_0)$?

Question

What is the meaning of $i$ in the following?

$$ (b_n \quad b_{n-1} \quad \cdots \quad b_0) \tag 1 $$ $i = n-1, n-2, \dots, 0$

Answer 1

i is the reversed list of indices of the sequence. For example if $n=2$, then the sequence becomes $(b_2 \ b_1 \ b_0)$, so $i = 2, 1, 0$