[R] How can I create a vector of vector?

[Jim]

Dear All,

How can I create a vector of vector in R?
for example, I would input the data as follows:
x[1] <- c(31,2,3)
x[2] <- c(1,2,5,34,5656)
x[3] <- c(211,3243,5,343,3)

Jim Liu