# [Ruby], <s>27</s> 25 bytes

<!-- language-all: lang-ruby -->

    a=1;a*=2while$><<a<<'+1/'

[Try it online!]

[Ruby]: https://www.ruby-lang.org/
[Try it online!]: https://tio.run/nexus/ruby#@59oa2idqGVrVJ6RmZOqYmdjk2hjo65tqK/@/z8A "Ruby – TIO Nexus"