How to create a matrix from vector returned by rep() function?

x=1:20

[1] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

rep(x,2)

[1] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

View(rep(x,2))

Having a problem with generating a 20 by 2 vector using the rep() function in R.

Instead of creating two columns, each running from 1 to 20, when I view the data in the R workspace, it is displayed as 40X1 vector i.e. 1-20 1-20.

How do you use the rep() function to create a repeated column vector of 20X2? Thank you.