Generating non-duplicate combination pairs in R

Question

Sorry for the non-descriptive title but I don\'t know whether there\'s a word for what I\'m trying to achieve.

Let\'s assume that I have a list of names of different

Answer 1

> x<-c('1','2','3','4')
> combn(x,2)
     [,1] [,2] [,3] [,4] [,5] [,6]
[1,] "1"  "1"  "1"  "2"  "2"  "3" 
[2,] "2"  "3"  "4"  "3"  "4"  "4"