What Comes Next?

What row of numbers comes next in this series?


1
11
21
1211
111221
312211
13112221

if you want more puzzles ask me

Nice 🙂
1113213211

Followed by 31131211131221

Originally posted by SJPinder
Nice 🙂
1113213211

go for it, sloppy, post them all.

This perl script outputs the first 10:

my ($num,$last) = (1,10);
for (my $n=1; $n<=$last; $n++) {
print "entry $n is $num \n";
my ($newnum, $lastchar, $count) = ('','',1);
foreach my $char (split //, $num) {
($lastchar = $char, next) unless $lastchar;
($count++, next) if $char eq $lastchar;
$newnum .= $count.$lastchar;
$lastchar = $char;
$count = 1;
}
$num = $newnum.$count.$lastchar;
}

That gives:

entry 1 is 1
entry 2 is 11
entry 3 is 21
entry 4 is 1211
entry 5 is 111221
entry 6 is 312211
entry 7 is 13112221
entry 8 is 1113213211
entry 9 is 31131211131221
entry 10 is 13211311123113112211

Originally posted by iamatiger
This perl script outputs the first 10:

my ($num,$last) = (1,10);
for (my $n=1; $n<=$last; $n++) {
print "entry $n is $num \n";
my ($newnum, $lastchar, $count) = ('','',1);
foreach my $char (split //, $num) {
($lastchar = $char, next) unless $lastchar;
($count++, next) if $char eq $lastchar;
...[text shortened]... 12221
entry 8 is 1113213211
entry 9 is 31131211131221
entry 10 is 13211311123113112211

Originally posted by sloppyb
can anyone go one step further can give entry 11?

Originally posted by sloppyb
can anyone go one step further can give entry 11?