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write_sequence

Language/Type: Python recursion recursive programming

Write a function write_sequence that accepts an integer n as a parameter and prints a symmetric sequence of n numbers with descending integers ending in 1 followed by ascending integers beginning with 1, as in the table below:

Call Output
write_sequence(1) 1
write_sequence(2) 1 1
write_sequence(3) 2 1 2
write_sequence(4) 2 1 1 2
write_sequence(5) 3 2 1 2 3
write_sequence(6) 3 2 1 1 2 3
write_sequence(7) 4 3 2 1 2 3 4
write_sequence(8) 4 3 2 1 1 2 3 4
write_sequence(9) 5 4 3 2 1 2 3 4 5
write_sequence(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 function should raise a ValueError if passed a value less than 1.

Function: Write a Python function as described, not a complete program.

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