Erlang install latest version (version 20+)

configure source
echo "deb http://packages.erlang-solutions.com/ubuntu trusty contrib" | sudo tee -a /etc/apt/sources.list.d/erlang_solutions.list
import key
wget -O- https:// dl.bintray.com/rabbitmq/Keys/rabbitmq-release-signing-key.asc | sudo apt-key add -
update and install
sudo apt-get update

sudo apt-get install erlang-nox

If you want to install a fixed erlang version, you can configure
# /etc/apt/preferences.d/erlang
Package: erlang*
Pin: version 1:20.1-1
Pin-Priority: 1000
Package: esl-erlang
Pin: version 1:20.1 -7
Pin-Priority: 1000
or
# /etc/apt/preferences.d/erlang
Package: erlang*
Pin: version 1:19.3-1
Pin-Priority: 1000
Package: esl-erlang
Pin: version 1:19.3-6
Pin -Priority: 1000