R Eigenvalues and Eigenvectors

Question

Let A be 4x4 matrix.

A = matrix(c(2,1,1,1,1,2,1,1,1,1,2,1,1,1,1,2), ncol=4, nrow=4, byrow=T)
eigen(A)

eigen(A)$values
[1] 5 1 1 1

eigen(A)$vectors

     [,1