The above entry h(3,5)=2/36 comes from the fact that (3,2) and (2,3) are the only points in S whose maximum number is 3 and those sum is 5 ; hence
h(3,5)=P(X=3,Y=5)=P{(3,2), (3,3)}=2/36
the other entries are obtained in a similar matter.
(wordt vervolgd)