This is a "one liner" with List::MoreUtils. Turning it into an example program:

#!/usr/bin/perl
use warnings;
use strict;

use List::MoreUtils qw/ uniq /;

my @TERMS = ( 1,2,7,2,4,5,3,4,2,2,4,27,81,3 );

my @INDEX = uniq @TERMS;

print "(", join( ',',@INDEX), ")\n";
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And the output is:

C:\Code>perl uniqarray.pl
(1,2,7,4,5,3,27,81)
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