I expect you've slapped your forehead by now, but in case you're still scratching it, check this out:

#!/usr/bin/perl -w

use strict;

my @dec_nums = ( 0 .. 255 );
my @hex_nums = ( 0x00 .. 0xFF );
my @oct_nums = ( 000 .. 0377 );

my $msg = "OMG! Inequality among %d. vs. 0x%02X vs. \\%03o on test #%d
+\n";

my $i;
for $i ( 0 .. $#dec_nums ) {
    if ( $i != $dec_nums[$i] or $i != $hex_nums[$i] or $i != $oct_nums
+[$i] ) {
        die sprintf( $msg, $dec_nums[$i], $hex_nums[$i], $oct_nums[$i]
+, $i );
    }
}

if ( @dec_nums != @hex_nums or @dec_nums != @oct_nums ) {
    die sprintf( $msg, scalar(@dec_nums), scalar(@hex_nums), 
                 scalar(@oct_nums), $i);
}

printf( "Whew! 0-%d. is the same as 0x00-0x%X and 000-0%o.\n",
        pop @dec_nums, pop @hex_nums, pop @oct_nums );
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