Can someone please help with with the coding (in R) of the following joint distribution question?

Task 1 (Discrete Joint Distribution) Consider the joint probability mass function of a pair of random variables (X, Y), Px,Y(1, j) = P(X = i, Y = j) for i, j = 1, ...,6. In R, we take px,y(i, j) = pXY [i, j] where pXY