If you are golfing then

@n = map { $n + 1 - $_, $_ } 1 .. $n / 2;
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if it the divisible by 4 constraint wasn't present then a little more care is required

use integer;
@n = map { $n + 1 - $_, $_ } 1 .. $n / 2;
push @n, $n / 2 + 1 if $n % 2;
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Update: As kindly pointed out by fellow monks I misread the specs. For the sake of completeness I give a correct (I hope) solution in the same vein as the previous offerings.

@n = map { $n + 2 - 2 * $_, 2 * $_ - 1, 2 * $_, $n + 1 - 2 * $_ } 1 ..
+ $n / 4;
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Unfortunately it's not as golfy but it is still cryptic looking;-)