Its halloween and every teen wants the halloween themed pi
phones coming out in october that comes with a suprise the day
of halloween with cool features but you must have the pi phone
before the day of halloween to find out, the manafactuar expects
4000 haunted pi phones to sell the first week of october and
expects the sales to increase by 10% Write an explicit and recursive
equation for the number of pi phone's the manufacturer predicts will sell
during the 4th week
