The Syracuse (also called Collatz or Hailstone) sequence is generated by starting with a natural number and repeatedly applying the following function until reaching 1:
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For example, the Syracuse sequence starting with 5 is: 5, 16, 8, 4, 2, 1. It is an open question in mathematics whether this sequence will always go to 1 for every possible starting value. Write a program that gets a starting value from the user and then prints the Syracuse sequence for that starting value.