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A3 / B6
A3 / B6
Part of
2011 Princeton University Math Competition
Problems
(1)
2011 PUMaC Algebra A3 / B6
Source:
9/24/2019
Shirley has a magical machine. If she inputs a positive even integer
n
n
n
, the machine will output
n
/
2
n/2
n
/2
, but if she inputs a positive odd integer
m
m
m
, the machine will output
m
+
3
m+3
m
+
3
. The machine keeps going by automatically using its output as a new input, stopping immediately before it obtains a number already processed. Shirley wants to create the longest possible output sequence possible with initial input at most
100
100
100
. What number should she input?
algebra