I do not understand your question. Your current script produces the following output: 
1: 33
2: 45
3: 57
4: 69
5: 81
...

[download]
I modified your code so that it would print out the value of the $a variable in hexadecimal notation (with a "0x" prefix), using the Perl built-in function printf: 
#!/usr/bin/env perl

use warnings;
use strict;
my $a=0x15;
for (my $i = 1; $i <= 100; $i++)
{
   $a+=0x0C;
   print "$i: ";
   printf "0x%x\n", $a;
}

[download]
This is the new output: 
1: 0x21
2: 0x2d
3: 0x39
4: 0x45
5: 0x51
...

[download]
If this is not the output you are looking for, please provide a small sample of your desired output.

Please also state a reason why you do not want to use printf.

In reply to Re: printing hexadecimal without printf by toolic
in thread printing hexadecimal without printf by tpais

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