Comment installer sage à partir d'un dépôt ?

Instructions à partir d'ici n'a pas fonctionné.

Instructions :

apt-add-repository -y ppa:aims/sagemath
apt-get update
apt-get install sagemath-upstream-binary

Après la dernière commande, j'obtiens :

$ sudo apt-get install sagemath-upstream-binary
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package sagemath-upstream-binary is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'sagemath-upstream-binary' has no installation candidate

Comment y remédier ?

MISE À JOUR

Vérifier la commande

$ sudo grep sage /etc/apt/sources.list.d/ -R
/etc/apt/sources.list.d/aims-sagemath-trusty.list.save:deb http://ppa.launchpad.net/aims/sagemath/ubuntu trusty main
/etc/apt/sources.list.d/aims-sagemath-trusty.list.save:# deb-src http://ppa.launchpad.net/aims/sagemath/ubuntu trusty main
/etc/apt/sources.list.d/aims-sagemath-trusty.list:deb http://ppa.launchpad.net/aims/sagemath/ubuntu trusty main
/etc/apt/sources.list.d/aims-sagemath-trusty.list:# deb-src http://ppa.launchpad.net/aims/sagemath/ubuntu trusty main
/etc/apt/sources.list.d/aims-sagemath-trusty.list:# deb-src http://ppa.launchpad.net/aims/sagemath/ubuntu trusty main