In case you are wondering this question, the formula is being work on under the project name: principia

To get all the latest ensemble formula, you can:

1. Install the principia-tools package from the ensemble ppa:

sudo add-apt-repository ppa:ensemble/ppa
sudo apt-get update
sudo apt-get install principia-tools

2. Then, create the /usr/share/principia-tools/formulas if it is not exist already and change the permission to yourselves:

sudo mkdir /usr/share/principia-tools/formulas
sudo chown -R `whoami` /usr/share/principia-tools/formulas

3. Now, let’s get all the formulas using:

principia getall

When that is done, run the ls /usr/share/principia-tools/formulas command to see all the formulas can be used by ensemble!

Reference:
Principia Tools Project:
https://launchpad.net/principia-tools

Ensemble Needs You!:
https://ensemble.ubuntu.com/Formulas
https://bugs.launchpad.net/principia/+bugs?field.tag=new-formula