Since during middle of each month, Bryce withdraws half of his amount. So at the end of each month, his balance is 1/2 times as compared to balance of his previous month.
The following recursive function represents the Brye's balance at end of each month:
[tex] a_{n}= \frac{1}{2}* a_{n-1} [/tex]
where [tex] a_{n-1} [/tex] is the account balance of previous month. And [tex] a_{n} [/tex] is the account balance of current month.
