bash-4.1$ ruby -e '$><<[*1..gets.to_i].reduce:*' <<< 5
-e:1: syntax error, unexpected tSYMBEG, expecting $end
$><<[*1..gets.to_i].reduce:*
                           ^

bash-4.1$ ruby -e '$><<[*1..gets.to_i].reduce :*' <<< 5
-e:1: syntax error, unexpected tSYMBEG, expecting $end
$><<[*1..gets.to_i].reduce :*
                            ^

bash-4.1$ ruby -e 'p RUBY_VERSION'
"1.9.3"