Given the OP's reference to the factors of a composite number thread, I interpreted 'use an unlimited number of times" to mean create numbers of the form
2**$i * 3**$j * 5**$k
with $i, $j, and $k as integers >= 0. The program I wrote generalizes this by handling an arbitrary number of arbitrary factors.
I don't know what you mean by 'factors of 3 lists', but if I guess that each list is a multiple of each factor, then I think that must not be right. The example given by the OP had 1 as the first member, but 1 is not any multiple 2, 3, or 5.
That said, there is an error my program :) 16 should be in the list even in my understanding of the problem. The mistake with is that the bound on the $depth I set was too low. In the harsh light of the morning, a safe bound is
my $depth = $seq_len;
But I am sure this bound can be made tighter, right after I have some tea :)
Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
Read Where should I post X? if you're not absolutely sure you're posting in the right place.
Please read these before you post! —
Posts may use any of the Perl Monks Approved HTML tags:
 a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
Outside of code tags, you may need to use entities for some characters:

For: 

Use: 
 &   & 
 <   < 
 >   > 
 [   [ 
 ]   ] 
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.

