[susam]

Here you go:

* http://mathb.in/13

* http://mathb.in/16

* http://mathb.in/20

* http://mathb.in/39

I wrote this tool all throughout a Saturday night 9 years ago and shared it with my friends on the next morning. The first URL (post 13) shows the first puzzle that was shared with the tool. The fourth URL (post 39) was the first post by someone I did not know. That's when I realized that people beyond my immediate friends' circle have begun using it now.