G'day Doozer,

If you're thinking about using the base number as a hash key, I assume it's unique. In which case, all of the numbers you've shown should match /${base}\d?$/; which they do:

$ alias perle
alias perle='perl -Mstrict -Mwarnings -Mautodie=:all -MCarp::Always -E
+'
[download]

$ perle '
    my $base = "1231600014";
    my @possibles = qw{
        012212316000140
        01221231600014
        2212316000140
        1221231600014
        221231600014
        1231600014
    };
    my $re = qr{${base}\d?$};

    for (@possibles) {
        if (/$re/) {
            say "$_ MATCH";
        }
        else {
            say "$_ NO MATCH";
        }
    }
'
012212316000140 MATCH
01221231600014 MATCH
2212316000140 MATCH
1221231600014 MATCH
221231600014 MATCH
1231600014 MATCH
[download]

That should get you started. I'm unsure on how you want to precede from here: look up dates from somewhere? determine a check digit somehow?

Your post seemed to suggest you knew the base code up-front. If not:

$ perle '
    my @possibles = qw{
        012212316000140
        01221231600014
        2212316000140
        1221231600014
        221231600014
        1231600014
    };

    my %re_map = (
        10 => qr{^(\d{10})$},
        12 => qr{^\d{2}(\d{10})$},
        13 => qr{^(?:(?:18|19|20|21|22)(\d{10})\d|\d{3}(\d{10}))$},
        14 => qr{^\d{4}(\d{10})$},
        15 => qr{^\d{4}(\d{10})\d$},
    );

    for (@possibles) {
        my $re = $re_map{+length};
        /$re/ and say $1 // $2;
    }
'
1231600014
1231600014
1231600014
1231600014
1231600014
1231600014
[download]

Both of those pieces of code are just showing techniques: adapt, as necessary, to your specific needs.