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You are working on problem set: Unit 4 ( Pause)

numberSequence

Language/Type: Java recursion

Write a recursive method named numberSequence that accepts an integer n as a parameter and prints a sequence of n integers, descending from n to 1 and then ascending back from 1 to n as in the table below:

Call Output
numberSequence(1); 1
numberSequence(2); 1 1
numberSequence(3); 2 1 2
numberSequence(4); 2 1 1 2
numberSequence(5); 3 2 1 2 3
numberSequence(6); 3 2 1 1 2 3
numberSequence(7); 4 3 2 1 2 3 4
numberSequence(8); 4 3 2 1 1 2 3 4
numberSequence(9); 5 4 3 2 1 2 3 4 5
numberSequence(10); 5 4 3 2 1 1 2 3 4 5

Notice that for odd numbers the sequence has a single 1 in the middle while for even values it has two 1s in the middle.

Your method should throw an IllegalArgumentException if passed a value less than 1.

Method: Write a Java method as described, not a complete program or class.

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