Comment 3 for bug 793831

I have opened an upstream bug / feature request for the double factorial.

I'd suggest you subscribe to the Gnome request I have opened, it would be helpful if you let them know about your specific need for implementing this operation, as the report I filed is quite generic and doesn't take into account your actual situation or use case.

https://bugzilla.gnome.org/show_bug.cgi?id=652061

Thanks again!