I love the fact that using numpy in Python it is very easy to define a matrix/array in a way that is very close to the mathematical definition.
Does R have a similar way of achieving this result?

import numpy as np

n = np.arange(4)    
m = np.arange(6)

## Now I will define the matrix N_mat[i,j]=m[i]*n[j] with 6 rows
## and 4 columns
N_mat = m[:,np.newaxis]*n[np.newaxis,:]