set pro /1*50/;
alias (pro,i,j,x,y);
parameter time(i,j);
time("1","5") = 8;
loop(i$(ord(i) > 5), loop(j,
  time(i,j) = sum((x,y)$(ord(x) eq ord(i)-5 and ord(y) eq ord(j)-5), time(x, y));
));
display time;

parameter time2(i,j);
time2("1","5") = 8;
loop(i$(ord(i) > 5), loop(j,
  time2(i,j) = time2(i-5,j-5);
));
time2(i,j) = time2(i,j) - time(i,j);
display time2;